diff --git a/lib/src/event.dart b/lib/src/event.dart
index d5be1222..f74747b6 100644
--- a/lib/src/event.dart
+++ b/lib/src/event.dart
@@ -32,6 +32,7 @@ abstract class RelationshipTypes {
   static const String reply = 'm.in_reply_to';
   static const String edit = 'm.replace';
   static const String reaction = 'm.annotation';
+  static const String thread = 'm.thread';
 }
 
 /// All data exchanged over Matrix is expressed as an "event". Typically each client action (e.g. sending a message) correlates with exactly one event.
@@ -45,6 +46,7 @@ class Event extends MatrixEvent {
   @Deprecated(
       'Use eventSender instead or senderFromMemoryOrFallback for a synchronous alternative')
   User get sender => senderFromMemoryOrFallback;
+
   User get senderFromMemoryOrFallback =>
       room.unsafeGetUserFromMemoryOrFallback(senderId);
 
@@ -72,6 +74,7 @@ class Event extends MatrixEvent {
       : null;
 
   MatrixEvent? _originalSource;
+
   MatrixEvent? get originalSource => _originalSource;
 
   Event({
@@ -789,6 +792,14 @@ class Event extends MatrixEvent {
     if (content.tryGet<Map<String, dynamic>>('m.relates_to') == null) {
       return null;
     }
+    if (content['m.relates_to'].containsKey('rel_type')) {
+      if (content
+              .tryGet<Map<String, dynamic>>('m.relates_to')
+              ?.tryGet<String>('rel_type') ==
+          RelationshipTypes.thread) {
+        return RelationshipTypes.thread;
+      }
+    }
     if (content['m.relates_to'].containsKey('m.in_reply_to')) {
       return RelationshipTypes.reply;
     }
diff --git a/lib/src/room.dart b/lib/src/room.dart
index d64fcd20..407d13b0 100644
--- a/lib/src/room.dart
+++ b/lib/src/room.dart
@@ -633,10 +633,16 @@ class Room {
       String? editEventId,
       bool parseMarkdown = true,
       bool parseCommands = true,
-      String msgtype = MessageTypes.Text}) {
+      String msgtype = MessageTypes.Text,
+      String? threadRootEventId,
+      String? threadLastEventId}) {
     if (parseCommands) {
       return client.parseAndRunCommand(this, message,
-          inReplyTo: inReplyTo, editEventId: editEventId, txid: txid);
+          inReplyTo: inReplyTo,
+          editEventId: editEventId,
+          txid: txid,
+          threadRootEventId: threadRootEventId,
+          threadLastEventId: threadLastEventId);
     }
     final event = <String, dynamic>{
       'msgtype': msgtype,
@@ -654,7 +660,11 @@ class Room {
       }
     }
     return sendEvent(event,
-        txid: txid, inReplyTo: inReplyTo, editEventId: editEventId);
+        txid: txid,
+        inReplyTo: inReplyTo,
+        editEventId: editEventId,
+        threadRootEventId: threadRootEventId,
+        threadLastEventId: threadLastEventId);
   }
 
   /// Sends a reaction to an event with an [eventId] and the content [key] into a room.
@@ -702,6 +712,8 @@ class Room {
     int? shrinkImageMaxDimension,
     MatrixImageFile? thumbnail,
     Map<String, dynamic>? extraContent,
+    String? threadRootEventId,
+    String? threadLastEventId,
   }) async {
     txid ??= client.generateUniqueTransactionId();
     sendingFilePlaceholders[txid] = file;
@@ -895,6 +907,8 @@ class Room {
       txid: txid,
       inReplyTo: inReplyTo,
       editEventId: editEventId,
+      threadRootEventId: threadRootEventId,
+      threadLastEventId: threadLastEventId,
     );
     sendingFilePlaceholders.remove(txid);
     sendingFileThumbnails.remove(txid);
@@ -972,6 +986,8 @@ class Room {
     String? txid,
     Event? inReplyTo,
     String? editEventId,
+    String? threadRootEventId,
+    String? threadLastEventId,
   }) async {
     // Create new transaction id
     final String messageID;
@@ -1010,6 +1026,25 @@ class Room {
         },
       };
     }
+
+    if (threadRootEventId != null) {
+      content['m.relates_to'] = {
+        'event_id': threadRootEventId,
+        'rel_type': RelationshipTypes.thread,
+        'is_falling_back': inReplyTo == null,
+        if (inReplyTo != null) ...{
+          'm.in_reply_to': {
+            'event_id': inReplyTo.eventId,
+          },
+        } else ...{
+          if (threadLastEventId != null)
+            'm.in_reply_to': {
+              'event_id': threadLastEventId,
+            },
+        }
+      };
+    }
+
     if (editEventId != null) {
       final newContent = content.copy();
       content['m.new_content'] = newContent;
diff --git a/lib/src/utils/commands_extension.dart b/lib/src/utils/commands_extension.dart
index 470821bc..ab33df88 100644
--- a/lib/src/utils/commands_extension.dart
+++ b/lib/src/utils/commands_extension.dart
@@ -30,14 +30,23 @@ extension CommandsClientExtension on Client {
 
   /// Parse and execute a string, `msg` is the input. Optionally `inReplyTo` is the event being
   /// replied to and `editEventId` is the eventId of the event being replied to
-  Future<String?> parseAndRunCommand(Room room, String msg,
-      {Event? inReplyTo, String? editEventId, String? txid}) async {
+  Future<String?> parseAndRunCommand(
+    Room room,
+    String msg, {
+    Event? inReplyTo,
+    String? editEventId,
+    String? txid,
+    String? threadRootEventId,
+    String? threadLastEventId,
+  }) async {
     final args = CommandArgs(
       inReplyTo: inReplyTo,
       editEventId: editEventId,
       msg: '',
       room: room,
       txid: txid,
+      threadRootEventId: threadRootEventId,
+      threadLastEventId: threadLastEventId,
     );
     if (!msg.startsWith('/')) {
       final sendCommand = commands['send'];
@@ -86,6 +95,8 @@ extension CommandsClientExtension on Client {
         editEventId: args.editEventId,
         parseCommands: false,
         txid: args.txid,
+        threadRootEventId: args.threadRootEventId,
+        threadLastEventId: args.threadLastEventId,
       );
     });
     addCommand('me', (CommandArgs args) async {
@@ -96,6 +107,8 @@ extension CommandsClientExtension on Client {
         msgtype: MessageTypes.Emote,
         parseCommands: false,
         txid: args.txid,
+        threadRootEventId: args.threadRootEventId,
+        threadLastEventId: args.threadLastEventId,
       );
     });
     addCommand('dm', (CommandArgs args) async {
@@ -119,6 +132,8 @@ extension CommandsClientExtension on Client {
         parseMarkdown: false,
         parseCommands: false,
         txid: args.txid,
+        threadRootEventId: args.threadRootEventId,
+        threadLastEventId: args.threadLastEventId,
       );
     });
     addCommand('html', (CommandArgs args) async {
@@ -270,11 +285,15 @@ class CommandArgs {
   Event? inReplyTo;
   Room room;
   String? txid;
+  String? threadRootEventId;
+  String? threadLastEventId;
 
   CommandArgs(
       {required this.msg,
       this.editEventId,
       this.inReplyTo,
       required this.room,
-      this.txid});
+      this.txid,
+      this.threadRootEventId,
+      this.threadLastEventId});
 }
diff --git a/test/commands_test.dart b/test/commands_test.dart
index f6575ec6..ba4ac670 100644
--- a/test/commands_test.dart
+++ b/test/commands_test.dart
@@ -17,6 +17,7 @@
  */
 
 import 'dart:convert';
+import 'dart:typed_data';
 
 import 'package:olm/olm.dart' as olm;
 import 'package:test/test.dart';
@@ -164,6 +165,105 @@ void main() {
       });
     });
 
+    test('thread', () async {
+      FakeMatrixApi.calledEndpoints.clear();
+      await room.sendTextEvent(
+        'thread',
+        threadRootEventId: '\$parent_event',
+        threadLastEventId: '\$parent_event',
+      );
+      final sent = getLastMessagePayload();
+      expect(sent, {
+        'msgtype': 'm.text',
+        'body': 'thread',
+        'm.relates_to': {
+          'rel_type': 'm.thread',
+          'event_id': '\$parent_event',
+          'is_falling_back': true,
+          'm.in_reply_to': {'event_id': '\$parent_event'}
+        },
+      });
+    });
+
+    test('thread_image', () async {
+      FakeMatrixApi.calledEndpoints.clear();
+      final testImage = MatrixFile(bytes: Uint8List(0), name: 'file.jpeg');
+      await room.sendFileEvent(
+        testImage,
+        threadRootEventId: '\$parent_event',
+        threadLastEventId: '\$parent_event',
+      );
+      final sent = getLastMessagePayload();
+      expect(sent, {
+        'msgtype': 'm.image',
+        'body': 'file.jpeg',
+        'filename': 'file.jpeg',
+        'url': 'mxc://example.com/AQwafuaFswefuhsfAFAgsw',
+        'info': {
+          'mimetype': 'image/jpeg',
+          'size': 0,
+        },
+        'm.relates_to': {
+          'rel_type': 'm.thread',
+          'event_id': '\$parent_event',
+          'is_falling_back': true,
+          'm.in_reply_to': {'event_id': '\$parent_event'}
+        },
+      });
+    });
+
+    test('thread_reply', () async {
+      FakeMatrixApi.calledEndpoints.clear();
+      await room.sendTextEvent('reply',
+          inReplyTo: Event(
+            eventId: '\$parent_event',
+            type: 'm.room.message',
+            content: {
+              'msgtype': 'm.text',
+              'body': 'reply',
+            },
+            originServerTs: DateTime.now(),
+            senderId: client.userID!,
+            room: room,
+          ),
+          threadRootEventId: '\$parent_event',
+          threadLastEventId: '\$parent_event');
+      final sent = getLastMessagePayload();
+      expect(sent, {
+        'msgtype': 'm.text',
+        'body': '> <@test:fakeServer.notExisting> reply\n\nreply',
+        'format': 'org.matrix.custom.html',
+        'formatted_body':
+            '<mx-reply><blockquote><a href="https://matrix.to/#/!1234:fakeServer.notExisting/\$parent_event">In reply to</a> <a href="https://matrix.to/#/@test:fakeServer.notExisting">@test:fakeServer.notExisting</a><br>reply</blockquote></mx-reply>reply',
+        'm.relates_to': {
+          'rel_type': 'm.thread',
+          'event_id': '\$parent_event',
+          'is_falling_back': false,
+          'm.in_reply_to': {'event_id': '\$parent_event'}
+        },
+      });
+    });
+
+    test('thread_different_event_ids', () async {
+      FakeMatrixApi.calledEndpoints.clear();
+      await room.sendTextEvent(
+        'thread',
+        threadRootEventId: '\$parent_event',
+        threadLastEventId: '\$last_event',
+      );
+      final sent = getLastMessagePayload();
+      expect(sent, {
+        'msgtype': 'm.text',
+        'body': 'thread',
+        'm.relates_to': {
+          'rel_type': 'm.thread',
+          'event_id': '\$parent_event',
+          'is_falling_back': true,
+          'm.in_reply_to': {'event_id': '\$last_event'}
+        },
+      });
+    });
+
     test('join', () async {
       FakeMatrixApi.calledEndpoints.clear();
       await room.sendTextEvent('/join !newroom:example.com');