diff --git a/booking.emails.inc b/booking.emails.inc
index 9f92b19..25864cc 100644
--- a/booking.emails.inc
+++ b/booking.emails.inc
@@ -31,17 +31,24 @@ function _booking_registration_email($nid, $balance_payment, $manual = false) {
  	
 	//send the registering person an email
 	$to = $node->booking_email;
-	$body = _booking_registration_email_generate($node, $waiting_list, $balance_payment, $manual);	
+	//$body = _booking_registration_email_generate($node, $waiting_list, $balance_payment, $manual);
+	//$params['body'] = $body;	
 	if ($balance_payment == TRUE) {
 		$subject = t('!event Payment Complete', array('!event' => $event->booking_eventname));
 	}
 	else {
 		$subject = t('!event Registration', array('!event' => $event->booking_eventname));
 	}
-
 	$params['subject'] = $subject;
-	$params['body'] = $body;
-	
+
+	//apply a theme to the HTML body of the email
+	$html_body = theme('booking_htmlmail_template', 
+		array('variables' => array(
+			'body' => _booking_registration_email_generate($node, $waiting_list, $balance_payment, $manual),
+		)
+	));
+	$params['body'] = $html_body;		
+
 	if (variable_get('booking_bcc_notify_email_workflow', 0) == 1) {	
 		$params['headers']['Bcc'] = variable_get('booking_notify_email', variable_get('site_mail', ini_get('sendmail_from')));
 	} 
diff --git a/booking.module b/booking.module
index 89d0cf8..f19ac32 100644
--- a/booking.module
+++ b/booking.module
@@ -869,6 +869,32 @@ function booking_mail($key, &$message, $params) {
   }
 }
 
+/**
+ * Implements hook_mail_alter()
+ */
+function booking_mail_alter(&$message) {
+	// $message['id'] comes from {module_name}_{email_key}
+  if($message['id'] == 'booking_registration_mail') {
+    $headers = array(
+      'MIME-Version' => '1.0',
+      'Content-Type' => 'text/html; charset=UTF-8; format=flowed',
+      'Content-Transfer-Encoding' => '8bit',
+      'X-Mailer' => 'Drupal',
+    );
+  }else{
+    $headers = array(
+      'MIME-Version' => '1.0',
+      'Content-Type' => 'text/plain; charset=UTF-8; format=flowed; delsp=yes',
+      'Content-Transfer-Encoding' => '8bit',
+      'X-Mailer' => 'Drupal',
+    );
+  }
+ 
+  //Overwrite header message header with Content-Type accommodating for html format
+  foreach($headers as $key => $value) {
+    $message['headers'][$key] = $value;
+  }
+}
 
 /**
  * Implements hook_library().