diff --git a/src/data/Thread.js b/src/data/Thread.js
index 5f4263b..f27359f 100644
--- a/src/data/Thread.js
+++ b/src/data/Thread.js
@@ -335,8 +335,15 @@ class Thread {
     }
 
     if (this.alert_id) {
-      await this.setAlert(null);
-      await this.postSystemMessage(`<@!${this.alert_id}> New message from ${this.user_name}`);
+      const ids = this.alert_id.split(",");
+      let mentions = "";
+
+      ids.forEach(id => {
+        mentions += `<@!${id}> `;
+      });
+
+      await this.deleteAlerts();
+      await this.postSystemMessage(`${mentions}New message from ${this.user_name}`);
     }
   }
 
@@ -594,14 +601,77 @@ class Thread {
    * @param {String} userId
    * @returns {Promise<void>}
    */
-  async setAlert(userId) {
+  async addAlert(userId) {
+    let alerts = await knex("threads")
+      .where("id", this.id)
+      .select("alert_id")
+      .first();
+    alerts = alerts.alert_id;
+
+    if (alerts == null) {
+      alerts = [userId]
+    } else {
+      alerts = alerts.split(",");
+      if (! alerts.includes(userId)) {
+        alerts.push(userId);
+      }
+    }
+
+    alerts = alerts.join(",");
     await knex("threads")
       .where("id", this.id)
       .update({
-        alert_id: userId
+        alert_id: alerts
       });
   }
 
+  /*
+   * @param {String} userId
+   * @returns {Promise<void>}
+   */
+  async removeAlert(userId) {
+    let alerts = await knex("threads")
+      .where("id", this.id)
+      .select("alert_id")
+      .first();
+    alerts = alerts.alert_id;
+
+    if (alerts != null) {
+      alerts = alerts.split(",");
+
+      for (let i = 0; i < alerts.length; i++) {
+        if (alerts[i] === userId) {
+          alerts.splice(i, 1);
+        }
+      }
+    } else {
+      return;
+    }
+
+    if (alerts.length === 0) {
+      alerts = null;
+    } else {
+      alerts = alerts.join(",");
+    }
+
+    await knex("threads")
+      .where("id", this.id)
+      .update({
+        alert_id: alerts
+      });
+  }
+
+  /**
+   * @returns {Promise<void>}
+   */
+  async deleteAlerts() {
+    await knex("threads")
+      .where("id", this.id)
+      .update({
+        alert_id: null
+      })
+  }
+
   /**
    * @param {Eris.Member} moderator
    * @param {ThreadMessage} threadMessage
diff --git a/src/modules/alert.js b/src/modules/alert.js
index 6f8f1ba..7976d7b 100644
--- a/src/modules/alert.js
+++ b/src/modules/alert.js
@@ -1,10 +1,10 @@
 module.exports = ({ bot, knex, config, commands }) => {
   commands.addInboxThreadCommand("alert", "[opt:string]", async (msg, args, thread) => {
     if (args.opt && args.opt.startsWith("c")) {
-      await thread.setAlert(null);
+      await thread.removeAlert(msg.author.id)
       await thread.postSystemMessage("Cancelled new message alert");
     } else {
-      await thread.setAlert(msg.author.id);
+      await thread.addAlert(msg.author.id);
       await thread.postSystemMessage(`Pinging ${msg.author.username}#${msg.author.discriminator} when this thread gets a new reply`);
     }
   });