diff --git a/README.org b/README.org
index 610b566..def6a14 100644
--- a/README.org
+++ b/README.org
@@ -136,6 +136,13 @@ Once signal-cli is running and Noise is installed:
 - =M-x noise-select-account= — pick which registered signal-cli account to use (sets =noise-account=)
 - =M-x noise-new-chat= — start a new conversation by searching contacts
 - =M-x noise-new-chat-sync-contacts= — re-sync contacts from signal-cli
+- =M-x noise-receive= — fetch new messages from signal-cli once
+
+While =noise-mode= is enabled, Noise polls signal-cli for new messages
+every =noise-receive-interval= seconds (default 5). Incoming messages,
+delivery/read receipts, typing indicators, and messages sent from your
+other linked devices are all stored locally and reflected in open
+buffers automatically.
 
 If signal-cli has more than one account registered, set =noise-account=
 to the phone number you want to use (E.164 format), or run
@@ -158,6 +165,20 @@ account it can stay nil.
 | =q=   | Quit chat list window     |
 | =C-x b= | Switch conversation (minibuffer) |
 
+**** Conversation buffer (*signal:NAME*)
+
+Compose inline at the =>= prompt at the bottom of the buffer. Message
+history above the prompt is read-only.
+
+| Key       | Action                          |
+|-----------+---------------------------------|
+| =RET=     | Send the composed message       |
+| =M-RET=   | Insert a newline (multi-line)   |
+| =C-c C-g= | Refresh conversation from store |
+
+Sent messages show a =✓= once sent and =✓✓= once delivered or read.
+When the contact is typing, the modeline shows =NAME is typing…=.
+
 **** Minibuffer switcher
 
 =M-x noise-switcher= (or =C-x b= from the chat list) opens a fuzzy
diff --git a/noise-chat-list.el b/noise-chat-list.el
index 09060e8..4a95133 100644
--- a/noise-chat-list.el
+++ b/noise-chat-list.el
@@ -9,6 +9,7 @@
 
 (require 'noise-db)
 (require 'noise-new-chat)
+(require 'noise-conversation)
 (require 'cl-lib)
 
 (defvar noise-chat-list-mode-map
@@ -113,21 +114,29 @@ CONV is a hash table with string keys from noise-db."
             preview-str "  "
             (propertize time-str 'face 'shadow))))
 
+(defun noise-chat-list--conversation-at-point ()
+  "Return the conversation on the current line, or nil."
+  (let ((conversations (noise-db-get-all-conversations))
+        (idx (1- (line-number-at-pos))))
+    (nth idx conversations)))
+
 (defun noise-chat-list-open ()
   "Open the conversation at point."
   (interactive)
-  (let* ((conversations (noise-db-get-all-conversations))
-         (idx (1- (line-number-at-pos)))
-         (conv (nth idx conversations)))
+  (let ((conv (noise-chat-list--conversation-at-point)))
     (if conv
-        (message "Open conversation: %s (not yet implemented)"
-                 (gethash "name" conv))
+        (noise-conversation-open (gethash "id" conv))
       (message "No conversation on this line."))))
 
 (defun noise-chat-list-mark-read ()
   "Mark the conversation at point as read."
   (interactive)
-  (message "Mark read: not yet connected to signal-cli"))
+  (let ((conv (noise-chat-list--conversation-at-point)))
+    (if conv
+        (progn
+          (noise-db-mark-conversation-read (gethash "id" conv))
+          (noise-chat-list--render))
+      (message "No conversation on this line."))))
 
 (defun noise-chat-list-refresh ()
   "Refresh the chat list (re-render from database)."
diff --git a/noise-conversation.el b/noise-conversation.el
new file mode 100644
index 0000000..95ab8f3
--- /dev/null
+++ b/noise-conversation.el
@@ -0,0 +1,249 @@
+;;; noise-conversation.el --- Conversation buffer for Noise -*- lexical-binding: t; -*-
+
+;;; Commentary:
+
+;; Provides the *signal:NAME* conversation buffer: full message history
+;; with day separators and delivery receipts, plus an inline compose
+;; prompt at the bottom.  RET sends, M-RET inserts a newline.
+
+;;; Code:
+
+(require 'noise-rpc)
+(require 'noise-db)
+(require 'cl-lib)
+
+(declare-function noise-chat-list--render "noise-chat-list")
+
+(defconst noise-conversation--width 71
+  "Column width used for day separators and receipt alignment.")
+
+(defvar-local noise-conversation--id nil
+  "ID of the conversation shown in this buffer.")
+
+(defvar-local noise-conversation--input-marker nil
+  "Marker at the start of the compose input area.")
+
+(defvar-local noise-conversation--typing nil
+  "Display name of the contact currently typing, or nil.")
+
+(defvar-local noise-conversation--typing-timer nil
+  "Timer that clears a stale typing indicator.")
+
+(defvar noise-conversation-mode-map
+  (let ((map (make-sparse-keymap)))
+    (define-key map (kbd "RET") #'noise-conversation-send)
+    (define-key map (kbd "M-RET") #'noise-conversation-newline)
+    (define-key map (kbd "C-c C-g") #'noise-conversation-refresh)
+    map)
+  "Keymap for `noise-conversation-mode'.")
+
+(define-derived-mode noise-conversation-mode text-mode "Signal Chat"
+  "Major mode for a Noise Signal conversation buffer.
+\\{noise-conversation-mode-map}"
+  :group 'noise)
+
+;;;###autoload
+(defun noise-conversation-open (conversation-id)
+  "Open (or switch to) the buffer for CONVERSATION-ID."
+  (noise-db-init)
+  (let ((conv (noise-db-get-conversation conversation-id)))
+    (unless conv
+      (user-error "No such conversation: %s" conversation-id))
+    (let* ((name (noise-conversation--display-name conv))
+           (buf (get-buffer-create (format "*signal:%s*" name))))
+      (switch-to-buffer buf)
+      (unless (derived-mode-p 'noise-conversation-mode)
+        (noise-conversation-mode))
+      (setq noise-conversation--id conversation-id)
+      (noise-db-mark-conversation-read conversation-id)
+      (noise-conversation--render)
+      (noise-conversation--refresh-chat-list)
+      buf)))
+
+(defun noise-conversation--display-name (conv)
+  "Pick the buffer display name for CONV, falling back to its ID."
+  (let ((name (gethash "name" conv)))
+    (if (and name (not (string-empty-p name))) name (gethash "id" conv))))
+
+(defun noise-conversation--buffer-for (conversation-id)
+  "Return the live buffer showing CONVERSATION-ID, or nil."
+  (cl-find-if (lambda (buf)
+                (with-current-buffer buf
+                  (and (derived-mode-p 'noise-conversation-mode)
+                       (equal noise-conversation--id conversation-id))))
+              (buffer-list)))
+
+(defun noise-conversation-refresh-for (conversation-id)
+  "Re-render the buffer for CONVERSATION-ID if one is open.
+Returns the buffer, or nil if none."
+  (when-let ((buf (noise-conversation--buffer-for conversation-id)))
+    (with-current-buffer buf
+      (noise-conversation--render))
+    buf))
+
+(defun noise-conversation-refresh ()
+  "Re-render the current conversation from the database."
+  (interactive)
+  (noise-conversation--render))
+
+;;; Rendering
+
+(defun noise-conversation--render ()
+  "Render message history and the compose prompt.
+Preserves any input already typed at the prompt."
+  (let ((input (noise-conversation--current-input))
+        (inhibit-read-only t)
+        (messages (noise-db-get-messages noise-conversation--id))
+        (last-day nil))
+    (erase-buffer)
+    (dolist (msg messages)
+      (let ((day (format-time-string
+                  "%a, %b %-e" (gethash "timestamp" msg))))
+        (unless (equal day last-day)
+          (insert (noise-conversation--day-separator day) "\n")
+          (setq last-day day))
+        (insert (noise-conversation--format-message msg) "\n")))
+    (insert " \n"
+            (propertize (make-string noise-conversation--width ?─)
+                        'face 'shadow)
+            "\n"
+            (propertize "> " 'face 'bold))
+    (add-text-properties (point-min) (point)
+                         '(read-only t
+                           front-sticky (read-only)
+                           rear-nonsticky (read-only)))
+    (setq noise-conversation--input-marker (point-marker))
+    (when input (insert input))
+    (goto-char (point-max))
+    (noise-conversation--update-modeline)
+    (set-buffer-modified-p nil)))
+
+(defun noise-conversation--current-input ()
+  "Return the text typed at the compose prompt, or nil before first render."
+  (when (and noise-conversation--input-marker
+             (marker-position noise-conversation--input-marker))
+    (buffer-substring-no-properties noise-conversation--input-marker
+                                    (point-max))))
+
+(defun noise-conversation--day-separator (day)
+  "Format DAY as a centered separator line like ──── Tue, Jun 9 ────."
+  (let* ((label (concat " " day " "))
+         (total (max 2 (- noise-conversation--width (length label))))
+         (left (/ total 2)))
+    (propertize (concat (make-string left ?─) label
+                        (make-string (- total left) ?─))
+                'face 'shadow)))
+
+(defun noise-conversation--format-message (msg)
+  "Format MSG (a hash table from noise-db) as a [HH:MM] sender> body line."
+  (let* ((source (or (gethash "source" msg) ""))
+         (me (string= source "me"))
+         (body (or (gethash "body" msg) ""))
+         (receipt (or (gethash "receipt_state" msg) ""))
+         (time-str (format-time-string "[%H:%M]" (gethash "timestamp" msg)))
+         (name (cond (me "me")
+                     ((string-empty-p source) "?")
+                     (t source))))
+    (when (eq (gethash "has_attachment" msg) 1)
+      (let ((file (file-name-nondirectory
+                   (or (gethash "attachment_path" msg) ""))))
+        (setq body (concat body (if (string-empty-p body) "" " ")
+                           (propertize
+                            (format "[attachment: %s — RET to view]" file)
+                            'face 'link)))))
+    (let ((line (concat (propertize time-str 'face 'shadow) " "
+                        (propertize name 'face 'bold)
+                        (propertize ">" 'face 'shadow) " "
+                        body)))
+      (if (and me (not (string-empty-p receipt)))
+          (let* ((check (if (string= receipt "sent") "✓" "✓✓"))
+                 (pad (max 1 (- noise-conversation--width
+                                (string-width line)
+                                (string-width check)))))
+            (concat line (make-string pad ?\s)
+                    (propertize check 'face 'success)))
+        line))))
+
+(defun noise-conversation--update-modeline ()
+  "Update the mode line with the E2E indicator and typing status."
+  (setq mode-line-format
+        (format " %s %s   %s%s ─ U:%%- ─ Bot ───"
+                (propertize "⌁ E2E" 'face 'success)
+                (propertize (buffer-name) 'face 'bold)
+                (if noise-conversation--typing
+                    (format "%s is typing…   " noise-conversation--typing)
+                  "")
+                "(Signal Chat)"))
+  (force-mode-line-update))
+
+;;; Composing and sending
+
+(defun noise-conversation-newline ()
+  "Insert a newline at the compose prompt without sending."
+  (interactive)
+  (insert "\n"))
+
+(defun noise-conversation-send ()
+  "Send the text composed at the prompt via signal-cli."
+  (interactive)
+  (let ((input (string-trim (or (noise-conversation--current-input) ""))))
+    (if (string-empty-p input)
+        (message "Nothing to send")
+      (let* ((conv (noise-db-get-conversation noise-conversation--id))
+             (group (string= (gethash "type" conv) "group"))
+             (result (if group
+                         (noise-rpc-call-for-account
+                          "send" :groupId noise-conversation--id :message input)
+                       (noise-rpc-call-for-account
+                        "send" :recipient (vector noise-conversation--id)
+                        :message input)))
+             (ts-ms (and (hash-table-p result) (gethash "timestamp" result)))
+             (ts (if ts-ms (/ ts-ms 1000.0) (float-time))))
+        (noise-db-insert-message noise-conversation--id
+                                 :timestamp ts
+                                 :source "me"
+                                 :body input
+                                 :receipt-state "sent")
+        (noise-conversation--clear-input)
+        (noise-conversation--render)
+        (noise-conversation--refresh-chat-list)))))
+
+(defun noise-conversation--clear-input ()
+  "Delete the text typed at the compose prompt."
+  (when (and noise-conversation--input-marker
+             (marker-position noise-conversation--input-marker))
+    (delete-region noise-conversation--input-marker (point-max))))
+
+;;; Typing indicator
+
+(defun noise-conversation-set-typing (conversation-id name action)
+  "Show or clear the typing indicator for CONVERSATION-ID.
+NAME is the contact typing; ACTION is signal-cli's STARTED or STOPPED."
+  (when-let ((buf (noise-conversation--buffer-for conversation-id)))
+    (with-current-buffer buf
+      (when noise-conversation--typing-timer
+        (cancel-timer noise-conversation--typing-timer)
+        (setq noise-conversation--typing-timer nil))
+      (if (equal action "STARTED")
+          (setq noise-conversation--typing name
+                noise-conversation--typing-timer
+                (run-with-timer 8 nil #'noise-conversation--clear-typing buf))
+        (setq noise-conversation--typing nil))
+      (noise-conversation--update-modeline))))
+
+(defun noise-conversation--clear-typing (buf)
+  "Clear the typing indicator in BUF after a timeout."
+  (when (buffer-live-p buf)
+    (with-current-buffer buf
+      (setq noise-conversation--typing nil
+            noise-conversation--typing-timer nil)
+      (noise-conversation--update-modeline))))
+
+(defun noise-conversation--refresh-chat-list ()
+  "Re-render the *signal* chat list buffer if it exists."
+  (when-let ((buf (get-buffer "*signal*")))
+    (with-current-buffer buf
+      (noise-chat-list--render))))
+
+(provide 'noise-conversation)
+;;; noise-conversation.el ends here
diff --git a/noise-db.el b/noise-db.el
index 7e586ec..06e85c5 100644
--- a/noise-db.el
+++ b/noise-db.el
@@ -249,6 +249,34 @@ Keyword arguments: :limit N, :offset N."
       (setq sql-params (nconc sql-params (list offset))))
     (apply #'noise-db--query sql-str sql-params)))
 
+(defun noise-db-mark-conversation-read (id)
+  "Set the unread count of conversation ID to zero."
+  (noise-db--exec "UPDATE conversations SET unread_count = 0 WHERE id = ?" id))
+
+(defun noise-db-increment-unread (id)
+  "Increment the unread count of conversation ID by one."
+  (noise-db--exec
+   "UPDATE conversations SET unread_count = unread_count + 1 WHERE id = ?" id))
+
+(defun noise-db-set-last-message-sender (id sender)
+  "Set the last-message SENDER shown in previews for conversation ID."
+  (noise-db--exec
+   "UPDATE conversations SET last_message_sender = ? WHERE id = ?" sender id))
+
+(defun noise-db-update-receipt-state (timestamp state)
+  "Upgrade the receipt state of own messages with TIMESTAMP to STATE.
+Only moves forward (sent < delivered < read), never downgrades."
+  (noise-db--exec
+   "UPDATE messages SET receipt_state = ?
+    WHERE source = 'me' AND timestamp = ?
+      AND (CASE receipt_state
+             WHEN 'read' THEN 3 WHEN 'delivered' THEN 2 WHEN 'sent' THEN 1
+             ELSE 0 END)
+        < (CASE ?
+             WHEN 'read' THEN 3 WHEN 'delivered' THEN 2 WHEN 'sent' THEN 1
+             ELSE 0 END)"
+   state timestamp state))
+
 (defun noise-db-get-conversation-members (conversation-id)
   "Get member contact IDs for CONVERSATION-ID."
   (noise-db--query
diff --git a/noise-new-chat.el b/noise-new-chat.el
index 43d3096..f81363b 100644
--- a/noise-new-chat.el
+++ b/noise-new-chat.el
@@ -11,6 +11,7 @@
 
 (require 'noise-rpc)
 (require 'noise-db)
+(require 'noise-conversation)
 (require 'cl-lib)
 
 (declare-function noise-chat-list--render "noise-chat-list")
@@ -72,9 +73,7 @@ The conversation ID for a direct chat is the contact ID itself."
   (when-let ((buf (get-buffer "*signal*")))
     (with-current-buffer buf
       (noise-chat-list--render)))
-  ;; Conversation buffers are not implemented yet; land on the chat list.
-  (message "Conversation with %s ready (conversation buffer not yet implemented)"
-           (or name contact-id)))
+  (noise-conversation-open contact-id))
 
 (defun noise-new-chat--candidate (contact)
   "Format CONTACT (a hash table from noise-db) as a completion candidate.
diff --git a/noise-receive.el b/noise-receive.el
new file mode 100644
index 0000000..e278203
--- /dev/null
+++ b/noise-receive.el
@@ -0,0 +1,224 @@
+;;; noise-receive.el --- Receive messages from signal-cli -*- lexical-binding: t; -*-
+
+;;; Commentary:
+
+;; Fetches new envelopes from signal-cli via the receive JSON-RPC method
+;; and stores them in the local database: incoming messages, messages
+;; sent from other linked devices (sync), delivery/read receipts, and
+;; typing indicators.  `noise-receive-start-polling' polls on a timer.
+
+;;; Code:
+
+(require 'noise-rpc)
+(require 'noise-db)
+(require 'noise-conversation)
+(require 'cl-lib)
+
+(declare-function noise-chat-list--render "noise-chat-list")
+
+(defcustom noise-receive-interval 5
+  "Seconds between automatic polls of signal-cli for new messages."
+  :type 'integer
+  :group 'noise)
+
+(defvar noise-receive--timer nil
+  "Active polling timer, or nil.")
+
+(defvar noise-receive--last-poll-error nil
+  "Last error message shown by the poller, to avoid repeating it.")
+
+;;;###autoload
+(defun noise-receive ()
+  "Fetch and store new envelopes from signal-cli.
+Returns the number of new messages stored."
+  (interactive)
+  (noise-db-init)
+  (let ((entries (noise-rpc-call-for-account "receive"))
+        (new 0)
+        (touched nil))
+    (seq-do
+     (lambda (entry)
+       (when-let ((envelope (noise-receive--field entry "envelope")))
+         (when-let ((conv-id (noise-receive--process-envelope envelope)))
+           (cl-incf new)
+           (cl-pushnew conv-id touched :test #'equal))))
+     entries)
+    (when touched
+      (dolist (conv-id touched)
+        (noise-conversation-refresh-for conv-id))
+      (when-let ((buf (get-buffer "*signal*")))
+        (with-current-buffer buf
+          (noise-chat-list--render))))
+    (when (called-interactively-p 'interactive)
+      (message "Received %d new message%s" new (if (= new 1) "" "s")))
+    new))
+
+;;;###autoload
+(defun noise-receive-start-polling ()
+  "Start polling signal-cli for new messages every `noise-receive-interval'."
+  (interactive)
+  (noise-receive-stop-polling)
+  (setq noise-receive--timer
+        (run-with-timer 0 noise-receive-interval #'noise-receive--poll)))
+
+(defun noise-receive-stop-polling ()
+  "Stop the message polling timer."
+  (interactive)
+  (when noise-receive--timer
+    (cancel-timer noise-receive--timer)
+    (setq noise-receive--timer nil)))
+
+(defun noise-receive--poll ()
+  "Poll for messages.
+Errors are shown in the echo area once per distinct error rather than
+on every poll, and never abort the timer."
+  (condition-case err
+      (progn
+        (noise-receive)
+        (setq noise-receive--last-poll-error nil))
+    (error
+     (let ((text (error-message-string err)))
+       (unless (equal text noise-receive--last-poll-error)
+         (setq noise-receive--last-poll-error text)
+         (message "Noise: receiving failed: %s%s"
+                  text
+                  (if (string-match-p "account parameter" text)
+                      " — set `noise-account' or run M-x noise-select-account"
+                    "")))))))
+
+;;; Envelope processing
+
+(defun noise-receive--field (obj key)
+  "Get KEY from hash table OBJ, treating JSON null as nil."
+  (when (hash-table-p obj)
+    (let ((v (gethash key obj)))
+      (unless (eq v :null) v))))
+
+(defun noise-receive--process-envelope (envelope)
+  "Process one ENVELOPE from signal-cli.
+Returns the conversation ID when a new message was stored, else nil."
+  (let* ((sender-id (or (noise-receive--field envelope "sourceNumber")
+                        (noise-receive--field envelope "source")
+                        (noise-receive--field envelope "sourceUuid")))
+         (sender-name (or (noise-receive--field envelope "sourceName")
+                          sender-id)))
+    (cond
+     ((noise-receive--field envelope "dataMessage")
+      (noise-receive--store-incoming
+       (noise-receive--field envelope "dataMessage") sender-id sender-name))
+     ((noise-receive--field envelope "syncMessage")
+      (noise-receive--store-sync
+       (noise-receive--field envelope "syncMessage")))
+     ((noise-receive--field envelope "receiptMessage")
+      (noise-receive--apply-receipt
+       (noise-receive--field envelope "receiptMessage") sender-id)
+      nil)
+     ((noise-receive--field envelope "typingMessage")
+      (noise-receive--apply-typing
+       (noise-receive--field envelope "typingMessage") sender-id sender-name)
+      nil))))
+
+(defun noise-receive--timestamp (ms)
+  "Convert a signal-cli millisecond timestamp MS to float seconds."
+  (/ ms 1000.0))
+
+(defun noise-receive--attachment-name (data-message)
+  "Return the filename of the first attachment in DATA-MESSAGE, or nil."
+  (let ((attachments (noise-receive--field data-message "attachments")))
+    (when (and attachments (> (length attachments) 0))
+      (let ((a (elt attachments 0)))
+        (or (noise-receive--field a "filename")
+            (noise-receive--field a "id"))))))
+
+(defun noise-receive--store-incoming (dm sender-id sender-name)
+  "Store an incoming data message DM from SENDER-ID / SENDER-NAME.
+Returns the conversation ID, or nil if there was nothing to store."
+  (let* ((body (or (noise-receive--field dm "message") ""))
+         (group (noise-receive--field dm "groupInfo"))
+         (group-id (and group (noise-receive--field group "groupId")))
+         (attachment (noise-receive--attachment-name dm))
+         (conv-id (or group-id sender-id))
+         (ts (noise-receive--timestamp
+              (noise-receive--field dm "timestamp"))))
+    (when (and conv-id (or (not (string-empty-p body)) attachment))
+      (when sender-id
+        (noise-db-upsert-contact sender-id :name sender-name))
+      (unless (noise-db-get-conversation conv-id)
+        (noise-db-upsert-conversation
+         conv-id
+         :type (if group-id "group" "direct")
+         :name (if group-id
+                   (or (noise-receive--field group "groupName") "")
+                 sender-name)
+         :members (and sender-id (list sender-id))))
+      (noise-db-insert-message conv-id
+                               :timestamp ts
+                               :source sender-name
+                               :body body
+                               :has-attachment (and attachment t)
+                               :attachment-path (or attachment ""))
+      ;; Direct chats show the preview without a sender prefix (the chat
+      ;; list only prefixes group senders and "me").
+      (unless group-id
+        (noise-db-set-last-message-sender conv-id ""))
+      (when (and attachment (string-empty-p body))
+        (noise-db-upsert-conversation
+         conv-id :last-message-preview (format "photo: %s" attachment)))
+      (let ((buf (noise-conversation--buffer-for conv-id)))
+        (if (and buf (get-buffer-window buf t))
+            (noise-db-mark-conversation-read conv-id)
+          (noise-db-increment-unread conv-id)))
+      conv-id)))
+
+(defun noise-receive--store-sync (sync)
+  "Store a message sent from another linked device, found in SYNC.
+Returns the conversation ID, or nil."
+  (when-let ((sent (noise-receive--field sync "sentMessage")))
+    (let* ((body (or (noise-receive--field sent "message") ""))
+           (group (noise-receive--field sent "groupInfo"))
+           (group-id (and group (noise-receive--field group "groupId")))
+           (dest (or (noise-receive--field sent "destinationNumber")
+                     (noise-receive--field sent "destination")
+                     (noise-receive--field sent "destinationUuid")))
+           (conv-id (or group-id dest))
+           (attachment (noise-receive--attachment-name sent))
+           (ts (noise-receive--timestamp
+                (noise-receive--field sent "timestamp"))))
+      (when (and conv-id (or (not (string-empty-p body)) attachment))
+        (unless (noise-db-get-conversation conv-id)
+          (noise-db-upsert-conversation
+           conv-id
+           :type (if group-id "group" "direct")
+           :name (if group-id "" (or dest ""))
+           :members (and dest (not group-id) (list dest))))
+        (noise-db-insert-message conv-id
+                                 :timestamp ts
+                                 :source "me"
+                                 :body body
+                                 :receipt-state "sent"
+                                 :has-attachment (and attachment t)
+                                 :attachment-path (or attachment ""))
+        conv-id))))
+
+(defun noise-receive--apply-receipt (rm sender-id)
+  "Apply receipt message RM from SENDER-ID to stored messages."
+  (let ((state (cond ((eq (noise-receive--field rm "isRead") t) "read")
+                     ((eq (noise-receive--field rm "isDelivery") t) "delivered")))
+        (timestamps (noise-receive--field rm "timestamps")))
+    (when (and state timestamps)
+      (seq-do (lambda (ts-ms)
+                (noise-db-update-receipt-state
+                 (noise-receive--timestamp ts-ms) state))
+              timestamps)
+      (when sender-id
+        (noise-conversation-refresh-for sender-id)))))
+
+(defun noise-receive--apply-typing (tm sender-id sender-name)
+  "Apply typing message TM from SENDER-ID / SENDER-NAME."
+  (let ((conv-id (or (noise-receive--field tm "groupId") sender-id))
+        (action (noise-receive--field tm "action")))
+    (when conv-id
+      (noise-conversation-set-typing conv-id sender-name action))))
+
+(provide 'noise-receive)
+;;; noise-receive.el ends here
diff --git a/noise-switcher.el b/noise-switcher.el
index 102b42c..ffa3253 100644
--- a/noise-switcher.el
+++ b/noise-switcher.el
@@ -10,6 +10,7 @@
 
 (require 'noise-db)
 (require 'noise-new-chat)
+(require 'noise-conversation)
 
 (defun noise-switcher ()
   "Switch to a Signal conversation via minibuffer completion.
@@ -31,7 +32,7 @@ Shows existing conversations and contacts without conversations."
         (if item
             (if (gethash "id" item)
                 ;; It's a conversation (has an id)
-                (message "Open conversation: %s (not yet implemented)" (gethash "name" item))
+                (noise-conversation-open (gethash "id" item))
               ;; It's a contact without a conversation — start one
               (noise-new-chat-with-contact (gethash "contact_id" item)
                                            (gethash "name" item)))
diff --git a/noise.el b/noise.el
index 2c10319..8c842fd 100644
--- a/noise.el
+++ b/noise.el
@@ -13,7 +13,9 @@
 
 (require 'noise-rpc)
 (require 'noise-chat-list)
+(require 'noise-conversation)
 (require 'noise-new-chat)
+(require 'noise-receive)
 
 (defgroup noise nil
   "Signal Messenger client for Emacs."
@@ -76,7 +78,10 @@ Queries the daemon for registered accounts and sets `noise-account'."
   :lighter " Noise"
   :group 'noise
   (if noise-mode
-      (noise-chat-list)
+      (progn
+        (noise-chat-list)
+        (noise-receive-start-polling))
+    (noise-receive-stop-polling)
     (message "Noise mode disabled")))
 
 (provide 'noise)
diff --git a/test/noise-conversation-test.el b/test/noise-conversation-test.el
new file mode 100644
index 0000000..25353a8
--- /dev/null
+++ b/test/noise-conversation-test.el
@@ -0,0 +1,155 @@
+;;; noise-conversation-test.el --- Tests for noise-conversation -*- lexical-binding: t; -*-
+
+(require 'ert)
+(require 'noise-conversation)
+
+(defvar noise-conversation-test--db
+  (expand-file-name "noise-conversation-test.db" temporary-file-directory))
+
+(defmacro noise-conversation-test--with-db (&rest body)
+  "Run BODY with a fresh test database and clean up conversation buffers."
+  `(let ((noise-db-file noise-conversation-test--db))
+     (unwind-protect
+         (progn
+           (when (file-exists-p noise-db-file)
+             (delete-file noise-db-file))
+           (noise-db-init)
+           ,@body)
+       (noise-db--close)
+       (when (file-exists-p noise-conversation-test--db)
+         (delete-file noise-conversation-test--db))
+       (dolist (buf (buffer-list))
+         (when (string-prefix-p "*signal:" (buffer-name buf))
+           (kill-buffer buf))))))
+
+(defun noise-conversation-test--seed ()
+  "Insert a direct conversation with Sarah and two messages."
+  (noise-db-upsert-contact "+1" :name "Sarah")
+  (noise-db-upsert-conversation "+1" :type "direct" :name "Sarah"
+                                :members '("+1"))
+  (noise-db-insert-message "+1" :timestamp 1717930000.0
+                           :source "Sarah" :body "are you coming?")
+  (noise-db-insert-message "+1" :timestamp 1717930100.0
+                           :source "me" :body "yes, leaving now"
+                           :receipt-state "delivered"))
+
+(ert-deftest noise-conversation-open-renders-history ()
+  "Opening a conversation renders messages, a day separator, and the prompt."
+  (noise-conversation-test--with-db
+   (noise-conversation-test--seed)
+   (with-current-buffer (noise-conversation-open "+1")
+     (let ((text (buffer-substring-no-properties (point-min) (point-max))))
+       (should (string-match-p "Sarah> are you coming\\?" text))
+       (should (string-match-p "me> yes, leaving now" text))
+       ;; day separator present
+       (should (string-match-p "─── .* ───" text))
+       ;; delivered receipt
+       (should (string-match-p "✓✓" text))
+       ;; compose prompt at the bottom
+       (should (string-match-p "^> " text))))))
+
+(ert-deftest noise-conversation-open-marks-read ()
+  "Opening a conversation resets its unread count."
+  (noise-conversation-test--with-db
+   (noise-conversation-test--seed)
+   (noise-db-upsert-conversation "+1" :unread-count 4)
+   (noise-conversation-open "+1")
+   (should (= 0 (gethash "unread_count" (noise-db-get-conversation "+1"))))))
+
+(ert-deftest noise-conversation-history-is-read-only ()
+  "Typing into the history region should fail; the prompt is editable."
+  (noise-conversation-test--with-db
+   (noise-conversation-test--seed)
+   (with-current-buffer (noise-conversation-open "+1")
+     (goto-char (point-min))
+     (should-error (insert "x"))
+     (goto-char (point-max))
+     (insert "hello")
+     (should (string= "hello" (noise-conversation--current-input))))))
+
+(ert-deftest noise-conversation-send-stores-and-clears ()
+  "Sending stores the message with the server timestamp and clears input."
+  (noise-conversation-test--with-db
+   (noise-conversation-test--seed)
+   (with-current-buffer (noise-conversation-open "+1")
+     (goto-char (point-max))
+     (insert "on my way")
+     (let (sent-params)
+       (cl-letf (((symbol-function 'noise-rpc-call-for-account)
+                  (lambda (method &rest params)
+                    (should (string= "send" method))
+                    (setq sent-params params)
+                    (let ((ht (make-hash-table :test 'equal)))
+                      (puthash "timestamp" 1717930200123 ht)
+                      ht))))
+         (noise-conversation-send))
+       (should (equal ["+1"] (plist-get sent-params :recipient)))
+       (should (string= "on my way" (plist-get sent-params :message))))
+     ;; input cleared, message rendered
+     (should (string= "" (noise-conversation--current-input)))
+     (let ((msgs (noise-db-get-messages "+1")))
+       (should (= 3 (length msgs)))
+       (let ((last (car (last msgs))))
+         (should (string= "me" (gethash "source" last)))
+         (should (string= "on my way" (gethash "body" last)))
+         (should (string= "sent" (gethash "receipt_state" last)))
+         (should (= 1717930200.123 (gethash "timestamp" last))))))))
+
+(ert-deftest noise-conversation-send-group-uses-group-id ()
+  "Sending in a group conversation uses the groupId parameter."
+  (noise-conversation-test--with-db
+   (noise-db-upsert-conversation "grp1" :type "group" :name "cycling crew")
+   (with-current-buffer (noise-conversation-open "grp1")
+     (goto-char (point-max))
+     (insert "saturday 7am?")
+     (let (sent-params)
+       (cl-letf (((symbol-function 'noise-rpc-call-for-account)
+                  (lambda (_method &rest params)
+                    (setq sent-params params)
+                    nil)))
+         (noise-conversation-send))
+       (should (string= "grp1" (plist-get sent-params :groupId)))
+       (should-not (plist-get sent-params :recipient))))))
+
+(ert-deftest noise-conversation-send-empty-does-nothing ()
+  "Sending with no input should not call signal-cli."
+  (noise-conversation-test--with-db
+   (noise-conversation-test--seed)
+   (with-current-buffer (noise-conversation-open "+1")
+     (cl-letf (((symbol-function 'noise-rpc-call-for-account)
+                (lambda (&rest _) (error "Should not be called"))))
+       (noise-conversation-send))
+     (should (= 2 (length (noise-db-get-messages "+1")))))))
+
+(ert-deftest noise-conversation-render-preserves-input ()
+  "Re-rendering keeps text already typed at the prompt."
+  (noise-conversation-test--with-db
+   (noise-conversation-test--seed)
+   (with-current-buffer (noise-conversation-open "+1")
+     (goto-char (point-max))
+     (insert "draft text")
+     (noise-conversation--render)
+     (should (string= "draft text" (noise-conversation--current-input))))))
+
+(ert-deftest noise-conversation-format-attachment ()
+  "Attachment messages render the [attachment: ...] hint."
+  (noise-conversation-test--with-db
+   (noise-conversation-test--seed)
+   (noise-db-insert-message "+1" :timestamp 1717930300.0
+                            :source "Sarah" :body ""
+                            :has-attachment t
+                            :attachment-path "IMG_2041.jpg")
+   (with-current-buffer (noise-conversation-open "+1")
+     (should (string-match-p "\\[attachment: IMG_2041\\.jpg — RET to view\\]"
+                             (buffer-string))))))
+
+(ert-deftest noise-conversation-typing-indicator ()
+  "Typing STARTED/STOPPED toggles the modeline indicator."
+  (noise-conversation-test--with-db
+   (noise-conversation-test--seed)
+   (with-current-buffer (noise-conversation-open "+1")
+     (noise-conversation-set-typing "+1" "Sarah" "STARTED")
+     (should (string= "Sarah" noise-conversation--typing))
+     (should (string-match-p "Sarah is typing…" mode-line-format))
+     (noise-conversation-set-typing "+1" "Sarah" "STOPPED")
+     (should-not noise-conversation--typing))))
diff --git a/test/noise-new-chat-test.el b/test/noise-new-chat-test.el
index 57b22c7..e2fb4cc 100644
--- a/test/noise-new-chat-test.el
+++ b/test/noise-new-chat-test.el
@@ -28,7 +28,10 @@
          (progn
            (noise-new-chat-test--setup)
            ,@body)
-       (noise-new-chat-test--teardown))))
+       (noise-new-chat-test--teardown)
+       (dolist (buf (buffer-list))
+         (when (string-prefix-p "*signal:" (buffer-name buf))
+           (kill-buffer buf))))))
 
 (defun noise-new-chat-test--contact (&rest kvs)
   "Build a hash table simulating a signal-cli contact from KVS pairs."
@@ -135,13 +138,19 @@
                             (noise-db-get-conversation-members "+1")))))))
 
 (ert-deftest noise-new-chat-with-contact-is-idempotent ()
-  "Starting a chat twice should not clobber the existing conversation."
+  "Starting a chat twice should not clobber the existing conversation.
+Opening the conversation marks it read, but history metadata survives."
   (noise-new-chat-test--with-db
-   (noise-db-upsert-conversation "+1" :type "direct" :name "Sarah"
-                                 :members '("+1")
-                                 :unread-count 3
-                                 :last-message-preview "hello")
-   (noise-new-chat-with-contact "+1" "Sarah")
-   (let ((conv (noise-db-get-conversation "+1")))
-     (should (= 3 (gethash "unread_count" conv)))
-     (should (string= "hello" (gethash "last_message_preview" conv))))))
+   (unwind-protect
+       (progn
+         (noise-db-upsert-conversation "+1" :type "direct" :name "Sarah"
+                                       :members '("+1")
+                                       :unread-count 3
+                                       :last-message-preview "hello")
+         (noise-new-chat-with-contact "+1" "Sarah")
+         (let ((conv (noise-db-get-conversation "+1")))
+           ;; opening the chat marks it read
+           (should (= 0 (gethash "unread_count" conv)))
+           (should (string= "hello" (gethash "last_message_preview" conv)))))
+     (when (get-buffer "*signal:Sarah*")
+       (kill-buffer "*signal:Sarah*")))))
diff --git a/test/noise-receive-poll-test.el b/test/noise-receive-poll-test.el
new file mode 100644
index 0000000..40387c1
--- /dev/null
+++ b/test/noise-receive-poll-test.el
@@ -0,0 +1,42 @@
+;;; noise-receive-poll-test.el --- Tests for the receive poller -*- lexical-binding: t; -*-
+
+(require 'ert)
+(require 'noise-receive)
+
+(ert-deftest noise-receive--poll-surfaces-error-once ()
+  "A failing poll messages the user once, not on every retry."
+  (let ((noise-receive--last-poll-error nil)
+        (messages nil))
+    (cl-letf (((symbol-function 'noise-receive)
+               (lambda ()
+                 (signal 'noise-rpc-error
+                         '("signal-cli error -32602: Method requires valid account parameter"))))
+              ((symbol-function 'message)
+               (lambda (fmt &rest args)
+                 (push (apply #'format fmt args) messages))))
+      (noise-receive--poll)
+      (noise-receive--poll))
+    (should (= 1 (length messages)))
+    (should (string-match-p "account parameter" (car messages)))
+    ;; the hint points at the fix
+    (should (string-match-p "noise-select-account" (car messages)))))
+
+(ert-deftest noise-receive--poll-recovers-and-resets ()
+  "After a successful poll, a recurring error is shown again."
+  (let ((noise-receive--last-poll-error nil)
+        (messages nil)
+        (fail t))
+    (cl-letf (((symbol-function 'noise-receive)
+               (lambda ()
+                 (when fail
+                   (signal 'noise-rpc-error '("connection refused")))
+                 0))
+              ((symbol-function 'message)
+               (lambda (fmt &rest args)
+                 (push (apply #'format fmt args) messages))))
+      (noise-receive--poll)            ; error -> message
+      (setq fail nil)
+      (noise-receive--poll)            ; success -> resets
+      (setq fail t)
+      (noise-receive--poll))           ; error again -> message again
+    (should (= 2 (length messages)))))
diff --git a/test/noise-receive-test.el b/test/noise-receive-test.el
new file mode 100644
index 0000000..9dec3dc
--- /dev/null
+++ b/test/noise-receive-test.el
@@ -0,0 +1,191 @@
+;;; noise-receive-test.el --- Tests for noise-receive -*- lexical-binding: t; -*-
+
+(require 'ert)
+(require 'noise-receive)
+
+(defvar noise-receive-test--db
+  (expand-file-name "noise-receive-test.db" temporary-file-directory))
+
+(defmacro noise-receive-test--with-db (&rest body)
+  "Run BODY with a fresh test database and clean up conversation buffers."
+  `(let ((noise-db-file noise-receive-test--db))
+     (unwind-protect
+         (progn
+           (when (file-exists-p noise-db-file)
+             (delete-file noise-db-file))
+           (noise-db-init)
+           ,@body)
+       (noise-db--close)
+       (when (file-exists-p noise-receive-test--db)
+         (delete-file noise-receive-test--db))
+       (dolist (buf (buffer-list))
+         (when (string-prefix-p "*signal:" (buffer-name buf))
+           (kill-buffer buf))))))
+
+(defun noise-receive-test--ht (&rest kvs)
+  "Build a hash table from KVS key/value pairs."
+  (let ((ht (make-hash-table :test 'equal)))
+    (while kvs
+      (puthash (car kvs) (cadr kvs) ht)
+      (setq kvs (cddr kvs)))
+    ht))
+
+(defun noise-receive-test--run (&rest envelopes)
+  "Run `noise-receive' against mocked ENVELOPES, returning its result."
+  (cl-letf (((symbol-function 'noise-rpc-call-for-account)
+             (lambda (method &rest _)
+               (should (string= "receive" method))
+               (apply #'vector
+                      (mapcar (lambda (e)
+                                (noise-receive-test--ht "envelope" e))
+                              envelopes)))))
+    (noise-receive)))
+
+(ert-deftest noise-receive-direct-message ()
+  "An incoming direct message creates contact, conversation, and message."
+  (noise-receive-test--with-db
+   (should (= 1 (noise-receive-test--run
+                 (noise-receive-test--ht
+                  "sourceNumber" "+1" "sourceName" "Sarah"
+                  "dataMessage" (noise-receive-test--ht
+                                 "timestamp" 1717930000000
+                                 "message" "are you coming?")))))
+   (should (string= "Sarah" (gethash "name" (noise-db-get-contact "+1"))))
+   (let ((conv (noise-db-get-conversation "+1")))
+     (should (string= "direct" (gethash "type" conv)))
+     (should (string= "Sarah" (gethash "name" conv)))
+     (should (= 1 (gethash "unread_count" conv)))
+     ;; direct chats have no sender prefix in the preview
+     (should (string= "" (gethash "last_message_sender" conv)))
+     (should (string= "are you coming?"
+                      (gethash "last_message_preview" conv))))
+   (let ((msg (car (noise-db-get-messages "+1"))))
+     (should (string= "Sarah" (gethash "source" msg)))
+     (should (= 1717930000.0 (gethash "timestamp" msg))))))
+
+(ert-deftest noise-receive-group-message ()
+  "An incoming group message creates a group conversation keyed by groupId."
+  (noise-receive-test--with-db
+   (noise-receive-test--run
+    (noise-receive-test--ht
+     "sourceNumber" "+2" "sourceName" "Priya"
+     "dataMessage" (noise-receive-test--ht
+                    "timestamp" 1717930000000
+                    "message" "saturday 7am, usual spot?"
+                    "groupInfo" (noise-receive-test--ht
+                                 "groupId" "grp1"
+                                 "groupName" "cycling crew"))))
+   (let ((conv (noise-db-get-conversation "grp1")))
+     (should (string= "group" (gethash "type" conv)))
+     (should (string= "cycling crew" (gethash "name" conv)))
+     ;; group previews keep the sender prefix
+     (should (string= "Priya" (gethash "last_message_sender" conv))))))
+
+(ert-deftest noise-receive-attachment-only-message ()
+  "An attachment-only message is stored and gets a photo preview."
+  (noise-receive-test--with-db
+   (noise-receive-test--run
+    (noise-receive-test--ht
+     "sourceNumber" "+1" "sourceName" "Sarah"
+     "dataMessage" (noise-receive-test--ht
+                    "timestamp" 1717930000000
+                    "message" :null
+                    "attachments" (vector (noise-receive-test--ht
+                                           "filename" "IMG_2041.jpg")))))
+   (let ((msg (car (noise-db-get-messages "+1"))))
+     (should (= 1 (gethash "has_attachment" msg)))
+     (should (string= "IMG_2041.jpg" (gethash "attachment_path" msg))))
+   (should (string= "photo: IMG_2041.jpg"
+                    (gethash "last_message_preview"
+                             (noise-db-get-conversation "+1"))))))
+
+(ert-deftest noise-receive-sync-message ()
+  "A sync sentMessage from another device is stored as from `me'."
+  (noise-receive-test--with-db
+   (noise-receive-test--run
+    (noise-receive-test--ht
+     "sourceNumber" "+me"
+     "syncMessage" (noise-receive-test--ht
+                    "sentMessage" (noise-receive-test--ht
+                                   "timestamp" 1717930000000
+                                   "destinationNumber" "+1"
+                                   "message" "sent from my phone"))))
+   (let ((msg (car (noise-db-get-messages "+1"))))
+     (should (string= "me" (gethash "source" msg)))
+     (should (string= "sent" (gethash "receipt_state" msg)))
+     (should (string= "sent from my phone" (gethash "body" msg))))
+   ;; own messages don't bump unread
+   (should (= 0 (gethash "unread_count" (noise-db-get-conversation "+1"))))))
+
+(ert-deftest noise-receive-delivery-receipt ()
+  "A delivery receipt upgrades the receipt state of the matching message."
+  (noise-receive-test--with-db
+   (noise-db-upsert-conversation "+1" :type "direct" :name "Sarah")
+   (noise-db-insert-message "+1" :timestamp 1717930000.0
+                            :source "me" :body "hi" :receipt-state "sent")
+   (noise-receive-test--run
+    (noise-receive-test--ht
+     "sourceNumber" "+1"
+     "receiptMessage" (noise-receive-test--ht
+                       "isDelivery" t "isRead" :false
+                       "timestamps" (vector 1717930000000))))
+   (should (string= "delivered"
+                    (gethash "receipt_state"
+                             (car (noise-db-get-messages "+1")))))))
+
+(ert-deftest noise-receive-receipt-never-downgrades ()
+  "A delivery receipt arriving after a read receipt is ignored."
+  (noise-receive-test--with-db
+   (noise-db-upsert-conversation "+1" :type "direct" :name "Sarah")
+   (noise-db-insert-message "+1" :timestamp 1717930000.0
+                            :source "me" :body "hi" :receipt-state "read")
+   (noise-receive-test--run
+    (noise-receive-test--ht
+     "sourceNumber" "+1"
+     "receiptMessage" (noise-receive-test--ht
+                       "isDelivery" t "isRead" :false
+                       "timestamps" (vector 1717930000000))))
+   (should (string= "read"
+                    (gethash "receipt_state"
+                             (car (noise-db-get-messages "+1")))))))
+
+(ert-deftest noise-receive-receipt-ignores-incoming-messages ()
+  "Receipts only apply to own messages, not the contact's."
+  (noise-receive-test--with-db
+   (noise-db-upsert-conversation "+1" :type "direct" :name "Sarah")
+   (noise-db-insert-message "+1" :timestamp 1717930000.0
+                            :source "Sarah" :body "hi")
+   (noise-receive-test--run
+    (noise-receive-test--ht
+     "sourceNumber" "+1"
+     "receiptMessage" (noise-receive-test--ht
+                       "isDelivery" t "isRead" :false
+                       "timestamps" (vector 1717930000000))))
+   (should (string= ""
+                    (gethash "receipt_state"
+                             (car (noise-db-get-messages "+1")))))))
+
+(ert-deftest noise-receive-typing-without-buffer ()
+  "Typing indicators for conversations without open buffers are harmless."
+  (noise-receive-test--with-db
+   (should (= 0 (noise-receive-test--run
+                 (noise-receive-test--ht
+                  "sourceNumber" "+1" "sourceName" "Sarah"
+                  "typingMessage" (noise-receive-test--ht
+                                   "action" "STARTED"
+                                   "timestamp" 1717930000000)))))))
+
+(ert-deftest noise-receive-refreshes-open-conversation ()
+  "Receiving a message re-renders an open conversation buffer."
+  (noise-receive-test--with-db
+   (noise-db-upsert-conversation "+1" :type "direct" :name "Sarah"
+                                 :members '("+1"))
+   (require 'noise-conversation)
+   (with-current-buffer (noise-conversation-open "+1")
+     (noise-receive-test--run
+      (noise-receive-test--ht
+       "sourceNumber" "+1" "sourceName" "Sarah"
+       "dataMessage" (noise-receive-test--ht
+                      "timestamp" 1717930000000
+                      "message" "new message here")))
+     (should (string-match-p "Sarah> new message here" (buffer-string))))))