diff --git a/README.md b/README.md
index 80f3c0e..b50c665 100644
--- a/README.md
+++ b/README.md
@@ -46,9 +46,12 @@ MATRIX_BOT_USERNAME=
 MATRIX_BOT_PASSWORD=
 MATRIX_AUTO_JOIN=true
 MATRIX_ENCRYPTION=true
+# Leave prefix blank to reply to all messages
+MATRIX_PREFIX=
 
 # needs to be ./storage/ if you aren't using Docker or /storage/ if you are.
 DATA_PATH=/storage/
+
 ```
 
 # Discussion
diff --git a/src/config.ts b/src/config.ts
index 509cc5a..8c3d38b 100644
--- a/src/config.ts
+++ b/src/config.ts
@@ -16,6 +16,7 @@ export const matrixAutojoin = process.env.MATRIX_AUTO_JOIN && process.env.MATRIX
 export const matrixEncryption = process.env.MATRIX_ENCRYPTION && process.env.MATRIX_ENCRYPTION.toLowerCase() === "true" as string;
 
 export const dataPath = process.env.DATA_PATH as string;
+export const matrixPrefix = process.env.MATRIX_PREFIX as string;
 
 /** ChatGPT specific stuff */
 export const openAiEmail = process.env.OPENAI_EMAIL as string;
@@ -51,6 +52,10 @@ if(matrixEncryption === undefined) {
   console.error("MATRIX_ENCRYPTION env variable is undefined");
   process.exit(1);
 }
+if(matrixPrefix === undefined) {
+  console.error("MATRIX_PREFIX env variable is undefined");
+  process.exit(1);
+}
 if(openAiEmail === undefined) {
   console.error("OPENAI_EMAIL env variable is undefined");
   process.exit(1);
diff --git a/src/handlers.ts b/src/handlers.ts
index eec6e50..3b3dd9e 100644
--- a/src/handlers.ts
+++ b/src/handlers.ts
@@ -1,6 +1,6 @@
 import { ChatGPTAPIBrowser } from "chatgpt";
 import { MatrixClient } from "matrix-bot-sdk";
-import { matrixBotUsername } from "./config.js";
+import { matrixBotUsername, matrixPrefix } from "./config.js";
 import { isEventAMessage } from "./utils.js";
 
 /**
@@ -19,7 +19,15 @@ export async function handleRoomEvent(client: MatrixClient, chatGPT: ChatGPTAPIB
     }
 
     if (isEventAMessage(event)) {
-      const question: string = event.content.body;
+      let question: string;
+      if (matrixPrefix){
+        if (!event.content.body.startsWith(matrixPrefix)){
+          return;
+        }
+        question = event.content.body.slice(matrixPrefix.length).trimStart();
+      } else {
+        question = event.content.body;
+      }
       if (question === undefined) {
         await client.sendReadReceipt(roomId, event.event_id);
         await client.sendText(roomId,