diff --git a/calendar/inc/class.calendar_category_report.inc.php b/calendar/inc/class.calendar_category_report.inc.php
index a7ce0a980b..d18a5db22b 100644
--- a/calendar/inc/class.calendar_category_report.inc.php
+++ b/calendar/inc/class.calendar_category_report.inc.php
@@ -347,7 +347,7 @@ class calendar_category_report extends calendar_ui{
 				//          ]
 				//
 				$result = array_replace_recursive($days_output, $min_days_output);
-				$csv_header =  array ();
+				$raw_csv = $csv_header =  array ();
 
 				// create csv header
 				foreach ($categories as $cat_id)
@@ -384,8 +384,20 @@ class calendar_category_report extends calendar_ui{
 					// last name
 					$n_family = array('n_family' => Api\Accounts::id2name($user_id, 'account_lastname')) ?
 							array('n_family' => Api\Accounts::id2name($user_id, 'account_lastname')) : array();
+					$raw_csv[] = $n_family + $n_given+ $cats_row;
+				}
+				// comparision function for usort
+				function compareByFamily ($key='n_family') {
+					return function ($a, $b) use ($key){
+						return strcasecmp($a[$key], $b[$key]);
+					};
+				}
+				usort($raw_csv, compareByFamily($content['sort_key']));
+
+				foreach ($raw_csv as &$row)
+				{
 					// printout each row into file
-					fputcsv($fp, array_values($n_family + $n_given+ $cats_row));
+					fputcsv($fp, array_values($row));
 				}
 				// echo out csv file
 				fpassthru($fp);
diff --git a/calendar/templates/default/category_report.xet b/calendar/templates/default/category_report.xet
index 649dba0fcc..7b3707e9da 100644
--- a/calendar/templates/default/category_report.xet
+++ b/calendar/templates/default/category_report.xet
@@ -60,6 +60,13 @@ Egroupware
 			<description value="Date range"/>
 			<date id="start" label="Start"/>
 			<date id="end" label="End"/>
+			<hbox>
+				<description value="sort by" label="%s:"/>
+				<vbox>
+					<radio id="sort_key" label="Last name" options="n_family"/>
+					<radio id="sort_key" label="First name" options="n_given"/>
+				</vbox>
+			</hbox>
 			<button id="button[report]" label="Report" onclick="app.calendar.category_report_submit" background_image="1" image="template"/>
 		</hbox>
 	</template>