diff --git a/matrix.go b/matrix.go
index 7a7dcd4..bdefff1 100644
--- a/matrix.go
+++ b/matrix.go
@@ -5,6 +5,8 @@ import (
 	"context"
 	"log"
 	"time"
+	"strings"
+	"fmt"
 
 	"maunium.net/go/mautrix"
 	"maunium.net/go/mautrix/event"
@@ -12,19 +14,38 @@ import (
 	"maunium.net/go/mautrix/format"
 )
 
+// MatrixMessage stores information about a matrix message.
 type MatrixMessage struct {
 	text string
 }
 
-// I/O queues
-var MatrixIn  []MatrixMessage
+// MatrixCommand stores information about a matrix chat command
+type MatrixCommand struct {
+	cmd string
+	callback func(ctx context.Context, evt *event.Event) string
+	description string
+}
+
+// Output queue
 var MatrixOut []MatrixMessage
 
+// ChatCommands
+var Chatcommands []MatrixCommand
+
 // sendMessage sends a message through Matrix
 func sendMessage(msg MatrixMessage) {
 	MatrixOut = append(MatrixOut, msg)
 }
 
+// registerChatCommand
+func registerChatCommand(cmd string, description string, callback func(ctx context.Context, evt *event.Event) string) {
+	Chatcommands = append(Chatcommands, MatrixCommand{
+		cmd: cmd,
+		callback: callback,
+		description: description,
+	})
+}
+
 // initMatrix starts a Matrix bot.
 func initMatrix() {
 	client, err := mautrix.NewClient(configuration.matrix.homeserver, "", "")
@@ -57,6 +78,26 @@ func initMatrix() {
 			}
 		}
 	})	
+	syncer.OnEventType(event.EventMessage, func(ctx context.Context, evt *event.Event) {
+		if evt.RoomID.String() == configuration.matrix.room_id {
+			for _, command := range Chatcommands {
+				if command.cmd == strings.TrimPrefix(evt.Content.AsMessage().Body, "!") {
+					out := command.callback(ctx, evt)
+					content := format.RenderMarkdown(out, true, false)
+					content.SetReply(evt)
+					client.SendMessageEvent(ctx, evt.RoomID, event.EventMessage, content)
+				}
+			}
+		}
+	})
+
+	registerChatCommand("help", "Show the help dialouge", func(ctx context.Context, evt *event.Event) string {
+		text := ""
+		for _,cmd := range Chatcommands {
+			text = fmt.Sprintf("%s- %s\n	%s\n", text, cmd.cmd, cmd.description)
+		}
+		return text
+	})
 
 	go func () {
 		for range time.Tick(time.Second * 3) {