diff --git a/booking.emails_admin.inc b/booking.emails_admin.inc
index 535625d..7d0a641 100644
--- a/booking.emails_admin.inc
+++ b/booking.emails_admin.inc
@@ -269,6 +269,7 @@ function booking_manual_email_form($form, &$form_state, $input_option = "")
 	//see http://www.jaypan.com/blog/themeing-drupal-7-forms-tables-checkboxes-or-radios	
 	$form = array();	
 	$options = array();
+	$preselection_options = array();
 	$values = array();
 	$group_text = "";
 	$prefix = t("<p>Send a manual email to people registered for this event.</p>");
@@ -282,6 +283,8 @@ function booking_manual_email_form($form, &$form_state, $input_option = "")
 	$email_options_array['initialtravelrequired'] = 'Initial Travel Form Required Email';
 	$email_options_array['remindertravelrequired'] = 'Reminder Travel Form Required Email';
 	$email_options_array['travelcomplete'] = 'Travel Form Complete Email';
+	$preselection_options['---'] = "---";
+	$preselection_options['bookedin'] = 'bookedin';
 
 	//add in the custom email types
 	for ($i = 1; $i <= variable_get('booking_custom_email_count','5'); $i++)
@@ -304,6 +307,17 @@ function booking_manual_email_form($form, &$form_state, $input_option = "")
 	$form['#attached']['css'] = array(
 	  drupal_get_path('module', 'booking') . '/booking.css',
 	);
+	//attach js for dynamically setting checkboxes
+	$form['#attached']['js'][] = drupal_get_path("module", "booking")."/booking.js" 
+	
+	//@todo add booking prefix
+	$form['email-type'] = array(
+		'#type' => 'select',
+		'#title' => t('Email Type'),
+		'#required' => TRUE,
+		'#default_value' => 'NULL',
+		'#options' => $email_options_array,
+	);	
 	
 	//@todo
 	/*
@@ -323,13 +337,24 @@ function booking_manual_email_form($form, &$form_state, $input_option = "")
 	http://jsfiddle.net/nanoquantumtech/dnhwz/ 
 	*/
 	
-	$form['email-type'] = array(
+	$form['booking-email-default-ids'] = array (
+		'#type' => 'hidden',
+		'#value' => "",
+		'#prefix' => '<div id="booking_email_default_ids_wrapper">',
+		'#suffix' => '</div>',
+	);	
+	
+	$form['booking-email-preselection'] = array(
 		'#type' => 'select',
-		'#title' => t('Email Type'),
-		'#required' => TRUE,
-		'#default_value' => 'NULL',
-		'#options' => $email_options_array,
-	);
+		'#title' => t('Preselect Attendees'),
+		'#options' => $preselection_options,
+		'#default_value' => '---',
+	    '#ajax' => array(
+	    	'event' => 'change',
+	    	'callback' => '_booking_email_get_default_selection_callback',
+			'wrapper' => 'booking_email_default_ids_wrapper',
+	    ),				
+	);	
 
 	$header = array(
 		'booking_nid' =>  array('data' => t('Id'), 'field' => 'nid', 'sort' => 'asc'),
@@ -434,6 +459,54 @@ function booking_manual_email_form($form, &$form_state, $input_option = "")
 		'form' => $form,
 	);
 }
+
+/**
+ * Callback to update hidden form value with default checkbox details
+ *
+ * Callback element needs only select the portion of the form to be updated.
+ * Since #ajax['callback'] return can be HTML or a renderable array (or an
+ * array of commands), we can just return a piece of the form.
+ * Source: http://www.maged.me/blog/drupal-7-execute-javascript-code-after-ajax-call
+ */
+function _booking_email_get_default_selection_callback($form, $form_state) {
+	global $event;
+	$defaults = array();
+	$replacementform_data = array();
+	
+	//get type of selection from $form_state['values']['booking-email-preselection']
+	$selection = $form_state['values']['booking-email-preselection'];
+	//load nodes
+	$people = booking_load_query(NULL, TRUE);
+	//populate $defaults based on type of selection
+	foreach ($people as $person) {
+		if ($selection == 'bookedin' && $person->booking_status == 1) {
+			$defaults[] = $person->nid;
+		}
+	}	
+	//set return value via drupal_json_encode($var)
+	$replacementform_data['booking-email-default-ids'] = array (
+		'#type' => 'hidden',
+		'#value' => drupal_json_encode($defaults),
+		'#prefix' => '<div id="booking_email_default_ids_wrapper">',
+		'#suffix' => '</div>',
+	);		
+	
+	return array(
+		'#type' => 'ajax',
+		'#commands' => array(
+			ajax_command_replace("#booking_email_default_ids_wrapper", render($replacementform_data['booking-email-default-ids'])),
+			array('command' => 'bookingEmailIDs'), // This will call the command nameOfCommand we just created in the JS file.
+		)
+	);
+}
+
+/**
+ * Callback to update hidden form value with default checkbox details
+ */
+function () {
+	
+}
+
 /**
  * Function to handle sending the manual emails 
  */
diff --git a/booking.js b/booking.js
new file mode 100644
index 0000000..228ccc8
--- /dev/null
+++ b/booking.js
@@ -0,0 +1,6 @@
+/**
+ * Special Effects AJAX framework command.
+ */
+Drupal.ajax.prototype.commands.bookingEmailIDs =  function(ajax, response, status) {
+  alert("Hello I'm Maged Eladawy...")  ; // this will be executed after the ajax call
+}
\ No newline at end of file
diff --git a/booking.studygroups.inc b/booking.studygroups.inc
index d11235b..763de88 100644
--- a/booking.studygroups.inc
+++ b/booking.studygroups.inc
@@ -608,6 +608,7 @@ function booking_studygroups_edit_form_submit($form, &$form_state) {
 						'booking_studygroup_role' => 0,
 				  ))
 				  ->execute();
+				  //@todo fix this - should be dynamic not hard coded
   				if ($key == 7)
 				{
   					booking_studygroups_process_colours();