diff --git a/app/services/UserService.php b/app/services/UserService.php
index 5842bcca4..de2647224 100644
--- a/app/services/UserService.php
+++ b/app/services/UserService.php
@@ -346,19 +346,28 @@ public function RequestPasswordReset($email) {
      * @return mixed
      */
     public function RequestSlackInvite($email) {
-        $ch = curl_init('http://slack-invite:3000/invite');
+        $url = 'https://' . SLACK_URL . '/api/users.admin.invite';
+
+        $body = [
+            'email' => $email,
+            'token' => SLACK_INVITE_TOKEN,
+            'set_active' => true
+        ];
+
+        $ch = curl_init($url);
         curl_setopt($ch, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
         curl_setopt($ch, CURLOPT_POST, 1);
         curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
-        curl_setopt($ch, CURLOPT_POSTFIELDS, 'email=' . $email);
+        curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($body));
         curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 1);
         curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
         curl_setopt($ch, CURLOPT_FORBID_REUSE, 1);
         curl_setopt($ch, CURLOPT_HTTPHEADER, ['Connection: Close']);
 
         $error = null;
+        $response = curl_exec($ch);
 
-        if (!($response = curl_exec($ch))) {
+        if (!$response) {
             $error = 'Error: Got ' . curl_error($ch) . " when request slack invite for email: '" . $email . "'";
         }
 
@@ -369,7 +378,30 @@ public function RequestSlackInvite($email) {
             return $error;
         }
 
-        return $response;
+        $json_data = json_decode($response, true);
+        // body looks like:
+        //   {"ok":true}
+        //       or
+        //   {"ok":false,"error":"already_invited"}
+
+        if ($json_data['ok']) {
+            return 'Invite sent';
+        }
+
+        $ErrorMap = [
+            'invalid_email' => 'The email you entered is an invalid email.',
+            'invalid_auth' => 'Something has gone wrong. Please contact a system administrator.'
+        ];
+
+        $error = $json_data['error'];
+
+        if ($error == 'already_invited' || $error == 'already_in_team') {
+            return 'Success! You were already invited.<br>Visit <a href="https://' . SLACK_URL . '">' . SLACK_URL . '</a>';
+        }
+
+        $error = $ErrorMap[$error] ?? $error;
+
+        return $error;
     }
 
     /**
diff --git a/conf/config.docker.ini.php b/conf/config.docker.ini.php
index 52cd4209f..930b6d825 100644
--- a/conf/config.docker.ini.php
+++ b/conf/config.docker.ini.php
@@ -43,8 +43,11 @@
 define('STRIPE_WEBHOOK_SECRET', NOMOS_STRIPE_WEBHOOK_SECRET);
 define('STRIPE_PRODUCTS', json_decode(NOMOS_STRIPE_PRODUCTS, true));
 
+define('SLACK_INVITE_TOKEN', NOMOS_SLACK_INVITE_TOKEN);
+define('SLACK_URL', NOMOS_SLACK_URL);
+
 /**
  * Show MySql Errors.
- * Not recomended for live site. true/false
+ * Not recomended for live site. true/false.
  */
 define('DEBUG', false);
diff --git a/docker/nomos.env.template b/docker/nomos.env.template
index b71993ed3..2a71364c2 100644
--- a/docker/nomos.env.template
+++ b/docker/nomos.env.template
@@ -18,6 +18,9 @@ NOMOS_STRIPE_API_KEY=
 NOMOS_STRIPE_WEBHOOK_SECRET=
 NOMOS_STRIPE_PRODUCTS=
 
+NOMOS_SLACK_INVITE_TOKEN=foobar
+NOMOS_SLACK_URL=vanhack.slack.com
+
 NOMOS_RABBITMQ_HOST=nomos-rabbitmq
 NOMOS_RABBITMQ_PORT=5672
 NOMOS_RABBITMQ_USER=nomos