diff --git a/apps/files_sharing/public.php b/apps/files_sharing/public.php
index acd5353faf..5672c78dc3 100644
--- a/apps/files_sharing/public.php
+++ b/apps/files_sharing/public.php
@@ -207,6 +207,7 @@ if ($linkItem) {
 		OCP\Util::addScript('files', 'fileactions');
 		$tmpl = new OCP\Template('files_sharing', 'public', 'base');
 		$tmpl->assign('uidOwner', $shareOwner);
+		$tmpl->assign('displayName', \OCP\User::getDisplayName($shareOwner));
 		$tmpl->assign('dir', $dir);
 		$tmpl->assign('filename', $file);
 		$tmpl->assign('mimetype', OC_Filesystem::getMimeType($path));
diff --git a/apps/files_sharing/templates/public.php b/apps/files_sharing/templates/public.php
index 35cca7c42d..71fca09ed6 100644
--- a/apps/files_sharing/templates/public.php
+++ b/apps/files_sharing/templates/public.php
@@ -6,9 +6,9 @@
 	<a href="<?php echo link_to('', 'index.php'); ?>" title="" id="owncloud"><img class="svg" src="<?php echo image_path('', 'logo-wide.svg'); ?>" alt="ownCloud" /></a>
 	<div class="header-right">
 	<?php if (isset($_['folder'])): ?>
-		<span id="details"><?php echo $l->t('%s shared the folder %s with you', array($_['uidOwner'], $_['filename'])) ?></span>
+		<span id="details"><?php echo $l->t('%s shared the folder %s with you', array($_['displayName'], $_['filename'])) ?></span>
 	<?php else: ?>
-		<span id="details"><?php echo $l->t('%s shared the file %s with you', array($_['uidOwner'], $_['filename'])) ?></span>
+		<span id="details"><?php echo $l->t('%s shared the file %s with you', array($_['displayName'], $_['filename'])) ?></span>
 	<?php endif; ?>
 		<?php if (!isset($_['folder']) || $_['allowZipDownload']): ?>
 			<a href="<?php echo $_['downloadURL']; ?>" class="button" id="download"><img class="svg" alt="Download" src="<?php echo OCP\image_path("core", "actions/download.svg"); ?>" /><?php echo $l->t('Download')?></a>
diff --git a/apps/user_ldap/user_ldap.php b/apps/user_ldap/user_ldap.php
index 6591d1d5fe..4928ad2e27 100644
--- a/apps/user_ldap/user_ldap.php
+++ b/apps/user_ldap/user_ldap.php
@@ -208,6 +208,50 @@ class USER_LDAP extends lib\Access implements \OCP\UserInterface {
 		return false;
 	}
 
+	/**
+	 * @brief get display name of the user
+	 * @param $uid user ID of the user
+	 * @return display name
+	 */
+	public function getDisplayName($uid) {
+		$cacheKey = 'getDisplayName'.$uid;
+		if(!is_null($displayName = $this->connection->getFromCache($cacheKey))) {
+			return $displayName;
+		}
+
+		$displayName = $this->readAttribute(
+			$this->username2dn($uid),
+			$this->connection->ldapUserDisplayName);
+
+		if($displayName && (count($displayName) > 0)) {
+			$this->connection->writeToCache($cacheKey, $displayName);
+			return $displayName[0];
+		}
+
+		return null;
+	}
+
+	/**
+	 * @brief Get a list of all display names
+	 * @returns array with  all displayNames (value) and the correspondig uids (key)
+	 *
+	 * Get a list of all display names and user ids.
+	 */
+	public function getDisplayNames($search = '', $limit = null, $offset = null) {
+		$cacheKey = 'getDisplayNames-'.$search.'-'.$limit.'-'.$offset;
+		if(!is_null($displayNames = $this->connection->getFromCache($cacheKey))) {
+			return $displayNames;
+		}
+
+		$displayNames = array();
+		$users = $this->getUsers($search, $limit, $offset);
+		foreach ($users as $user) {
+			$displayNames[$user] = $this->getDisplayName($user);
+		}
+		$this->connection->writeToCache($cacheKey, $displayNames);
+		return $displayNames;
+	}
+
 		/**
 	* @brief Check if backend implements actions
 	* @param $actions bitwise-or'ed actions
diff --git a/core/ajax/share.php b/core/ajax/share.php
index 077baa8ba5..6704a00c5a 100644
--- a/core/ajax/share.php
+++ b/core/ajax/share.php
@@ -72,6 +72,7 @@ if (isset($_POST['action']) && isset($_POST['itemType']) && isset($_POST['itemSo
 		case 'email':
 			// read post variables
 			$user = OCP\USER::getUser();
+			$displayName = OCP\User::getDisplayName();
 			$type = $_POST['itemType'];
 			$link = $_POST['link'];
 			$file = $_POST['file'];
@@ -81,13 +82,13 @@ if (isset($_POST['action']) && isset($_POST['itemType']) && isset($_POST['itemSo
 			$l = OC_L10N::get('core');
 
 			// setup the email
-			$subject = (string)$l->t('User %s shared a file with you', $user);
+			$subject = (string)$l->t('User %s shared a file with you', $displayName);
 			if ($type === 'dir')
-				$subject = (string)$l->t('User %s shared a folder with you', $user);
+				$subject = (string)$l->t('User %s shared a folder with you', $displayName);
 
-			$text = (string)$l->t('User %s shared the file "%s" with you. It is available for download here: %s', array($user, $file, $link));
+			$text = (string)$l->t('User %s shared the file "%s" with you. It is available for download here: %s', array($displayName, $file, $link));
 			if ($type === 'dir')
-				$text = (string)$l->t('User %s shared the folder "%s" with you. It is available for download here: %s', array($user, $file, $link));
+				$text = (string)$l->t('User %s shared the folder "%s" with you. It is available for download here: %s', array($displayName, $file, $link));
 
 
 			$default_from = OCP\Util::getDefaultEmailAddress('sharing-noreply');
@@ -158,14 +159,14 @@ if (isset($_POST['action']) && isset($_POST['itemType']) && isset($_POST['itemSo
 				while ($count < 4 && count($users) == $limit) {
 					$limit = 4 - $count;
 					if ($sharePolicy == 'groups_only') {
-						$users = OC_Group::usersInGroups($groups, $_GET['search'], $limit, $offset);
+						$users = OC_Group::DisplayNamesInGroups($groups, $_GET['search'], $limit, $offset);
 					} else {
-						$users = OC_User::getUsers($_GET['search'], $limit, $offset);
+						$users = OC_User::getDisplayNames($_GET['search'], $limit, $offset);
 					}
 					$offset += $limit;
-					foreach ($users as $user) {
-						if ((!isset($_GET['itemShares']) || !is_array($_GET['itemShares'][OCP\Share::SHARE_TYPE_USER]) || !in_array($user, $_GET['itemShares'][OCP\Share::SHARE_TYPE_USER])) && $user != OC_User::getUser()) {
-							$shareWith[] = array('label' => $user, 'value' => array('shareType' => OCP\Share::SHARE_TYPE_USER, 'shareWith' => $user));
+					foreach ($users as $uid => $displayName) {
+						if ((!isset($_GET['itemShares']) || !is_array($_GET['itemShares'][OCP\Share::SHARE_TYPE_USER]) || !in_array($uid, $_GET['itemShares'][OCP\Share::SHARE_TYPE_USER])) && $uid != OC_User::getUser()) {
+							$shareWith[] = array('label' => $displayName, 'value' => array('shareType' => OCP\Share::SHARE_TYPE_USER, 'shareWith' => $uid));
 							$count++;
 						}
 					}
diff --git a/core/js/share.js b/core/js/share.js
index b9b7201dd8..0c45765bd8 100644
--- a/core/js/share.js
+++ b/core/js/share.js
@@ -165,9 +165,9 @@ OC.Share={
 		var html = '<div id="dropdown" class="drop" data-item-type="'+itemType+'" data-item-source="'+itemSource+'">';
 		if (data !== false && data.reshare !== false && data.reshare.uid_owner !== undefined) {
 			if (data.reshare.share_type == OC.Share.SHARE_TYPE_GROUP) {
-				html += '<span class="reshare">'+t('core', 'Shared with you and the group {group} by {owner}', {group: data.reshare.share_with, owner: data.reshare.uid_owner})+'</span>';
+				html += '<span class="reshare">'+t('core', 'Shared with you and the group {group} by {owner}', {group: data.reshare.share_with, owner: data.reshare.displayname_owner})+'</span>';
 			} else {
-				html += '<span class="reshare">'+t('core', 'Shared with you by {owner}', {owner: data.reshare.uid_owner})+'</span>';
+				html += '<span class="reshare">'+t('core', 'Shared with you by {owner}', {owner: data.reshare.displayname_owner})+'</span>';
 			}
 			html += '<br />';
 		}
@@ -203,9 +203,9 @@ OC.Share={
 						OC.Share.showLink(share.token, share.share_with, itemSource);
 					} else {
 						if (share.collection) {
-							OC.Share.addShareWith(share.share_type, share.share_with, share.permissions, possiblePermissions, share.collection);
+							OC.Share.addShareWith(share.share_type, share.share_with, share.share_with_displayname, share.permissions, possiblePermissions, share.collection);
 						} else {
-							OC.Share.addShareWith(share.share_type, share.share_with, share.permissions, possiblePermissions, false);
+							OC.Share.addShareWith(share.share_type, share.share_with, share.share_with_displayname,  share.permissions, possiblePermissions, false);
 						}
 					}
 					if (share.expiration != null) {
@@ -245,7 +245,7 @@ OC.Share={
 				// Default permissions are Read and Share
 				var permissions = OC.PERMISSION_READ | OC.PERMISSION_SHARE;
 				OC.Share.share(itemType, itemSource, shareType, shareWith, permissions, function() {
-					OC.Share.addShareWith(shareType, shareWith, permissions, possiblePermissions);
+					OC.Share.addShareWith(shareType, shareWith, selected.item.label, permissions, possiblePermissions);
 					$('#shareWith').val('');
 					OC.Share.updateIcon(itemType, itemSource);
 				});
@@ -274,7 +274,7 @@ OC.Share={
 			}
 		});
 	},
-	addShareWith:function(shareType, shareWith, permissions, possiblePermissions, collection) {
+	addShareWith:function(shareType, shareWith, shareWithDisplayName, permissions, possiblePermissions, collection) {
 		if (!OC.Share.itemShares[shareType]) {
 			OC.Share.itemShares[shareType] = [];
 		}
@@ -289,7 +289,7 @@ OC.Share={
 			if (collectionList.length > 0) {
 				$(collectionList).append(', '+shareWith);
 			} else {
-				var html = '<li style="clear: both;" data-collection="'+item+'">'+t('core', 'Shared in {item} with {user}', {'item': item, user: shareWith})+'</li>';
+				var html = '<li style="clear: both;" data-collection="'+item+'">'+t('core', 'Shared in {item} with {user}', {'item': item, user: shareWithDisplayName})+'</li>';
 				$('#shareWithList').prepend(html);
 			}
 		} else {
@@ -312,9 +312,9 @@ OC.Share={
 			var html = '<li style="clear: both;" data-share-type="'+shareType+'" data-share-with="'+shareWith+'" title="' + shareWith + '">';
 			html += '<a href="#" class="unshare" style="display:none;"><img class="svg" alt="'+t('core', 'Unshare')+'" src="'+OC.imagePath('core', 'actions/delete')+'"/></a>';
 			if(shareWith.length > 14){
-				html += shareWith.substr(0,11) + '...';
+				html += shareWithDisplayName.substr(0,11) + '...';
 			}else{
-				html += shareWith;
+				html += shareWithDisplayName;
 			}
 			if (possiblePermissions & OC.PERMISSION_CREATE || possiblePermissions & OC.PERMISSION_UPDATE || possiblePermissions & OC.PERMISSION_DELETE) {
 				if (editChecked == '') {
diff --git a/core/templates/layout.user.php b/core/templates/layout.user.php
index 18291e0f84..2886c3c5a2 100644
--- a/core/templates/layout.user.php
+++ b/core/templates/layout.user.php
@@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html>
 	<head>
-		<title><?php echo isset($_['application']) && !empty($_['application'])?$_['application'].' | ':'' ?>ownCloud <?php echo OC_User::getUser()?' ('.OC_User::getUser().') ':'' ?></title>
+		<title><?php echo isset($_['application']) && !empty($_['application'])?$_['application'].' | ':'' ?>ownCloud <?php echo OC_User::getDisplayName()?' ('.OC_Util::sanitizeHTML(OC_User::getDisplayName()).') ':'' ?></title>
 		<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
 		<meta name="apple-itunes-app" content="app-id=543672169">
 		<link rel="shortcut icon" href="<?php echo image_path('', 'favicon.png'); ?>" /><link rel="apple-touch-icon-precomposed" href="<?php echo image_path('', 'favicon-touch.png'); ?>" />
diff --git a/db_structure.xml b/db_structure.xml
index db43ef2114..e878eac769 100644
--- a/db_structure.xml
+++ b/db_structure.xml
@@ -679,6 +679,14 @@
 				<length>64</length>
 			</field>
 
+			<field>
+				<name>displayname</name>
+				<type>text</type>
+				<default></default>
+				<notnull>true</notnull>
+				<length>64</length>
+			</field>
+
 			<field>
 				<name>password</name>
 				<type>text</type>
diff --git a/lib/group.php b/lib/group.php
index ed9482418b..5afef76936 100644
--- a/lib/group.php
+++ b/lib/group.php
@@ -286,4 +286,33 @@ class OC_Group {
 		}
 		return $users;
 	}
+	
+	/**
+	 * @brief get a list of all display names in a group
+	 * @returns array with display names (value) and user ids(key)
+	 */
+	public static function displayNamesInGroup($gid, $search = '', $limit = -1, $offset = 0) {
+		$displayNames=array();
+		foreach(self::$_usedBackends as $backend) {
+			$displayNames = array_merge($backend->displayNamesInGroup($gid, $search, $limit, $offset), $displayNames);
+		}
+		return $displayNames;
+	}
+	
+	/**
+	 * @brief get a list of all display names in several groups
+	 * @param array $gids
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return array with display names (Key) user ids (value)
+	 */
+	public static function displayNamesInGroups($gids, $search = '', $limit = -1, $offset = 0) {
+		$displayNames = array();
+		foreach ($gids as $gid) {
+			// TODO Need to apply limits to groups as total
+			$displayNames = array_merge(array_diff(self::displayNamesInGroup($gid, $search, $limit, $offset), $displayNames), $displayNames);
+		}
+		return $displayNames;
+	}
 }
diff --git a/lib/group/backend.php b/lib/group/backend.php
index 9ff432d066..4f6570c3be 100644
--- a/lib/group/backend.php
+++ b/lib/group/backend.php
@@ -133,5 +133,23 @@ abstract class OC_Group_Backend implements OC_Group_Interface {
 	public function usersInGroup($gid, $search = '', $limit = -1, $offset = 0) {
 		return array();
 	}
+	
+	/**
+	 * @brief get a list of all display names in a group
+	 * @param string $gid
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return array with display names (value) and user ids (key)
+	 */
+	public function DisplayNamesInGroup($gid, $search = '', $limit = -1, $offset = 0) {
+		$displayNames = '';
+		$users = $this->usersInGroup($gid, $search, $limit, $offset);
+		foreach ( $users as $user ) {
+			$DisplayNames[$user] = $user;
+		}
+			
+		return $DisplayNames;
+	}
 
 }
diff --git a/lib/group/database.php b/lib/group/database.php
index 6eca98ba01..c5dd402b21 100644
--- a/lib/group/database.php
+++ b/lib/group/database.php
@@ -208,4 +208,32 @@ class OC_Group_Database extends OC_Group_Backend {
 		}
 		return $users;
 	}
+	
+	/**
+	 * @brief get a list of all display names in a group
+	 * @param string $gid
+	 * @param string $search
+	 * @param int $limit
+	 * @param int $offset
+	 * @return array with display names (value) and user ids (key)
+	 */
+	public function DisplayNamesInGroup($gid, $search = '', $limit = -1, $offset = 0) {
+		$displayNames = '';
+		/*
+		
+		SELECT Persons.LastName, Persons.FirstName, Orders.OrderNo
+		FROM Persons
+		INNER JOIN Orders
+		ON Persons.P_Id=Orders.P_Id
+		ORDER BY Persons.LastName
+		*/
+		$stmt = OC_DB::prepare('SELECT `*PREFIX*users`.`uid`, `*PREFIX*users`.`displayname` FROM `*PREFIX*users` INNER JOIN `*PREFIX*group_user` ON `*PREFIX*group_user`.`uid` = `*PREFIX*users`.`uid`  WHERE `gid` = ? AND `*PREFIX*group_user.uid` LIKE ?', $limit, $offset);
+		$result = $stmt->execute(array($gid, $search.'%'));
+		$users = array();
+		while ($row = $result->fetchRow()) {
+			$displayName = trim($row['displayname'], ' ');
+			$displayNames[$row['uid']] = empty($displayName) ? $row['uid'] : $displayName;
+		}
+		return $displayNames;
+	}
 }
diff --git a/lib/public/share.php b/lib/public/share.php
index cda583aa07..e1d77e652d 100644
--- a/lib/public/share.php
+++ b/lib/public/share.php
@@ -946,6 +946,15 @@ class Share {
 					continue;
 				}
 			}
+
+			// Add display names to result
+			if ( isset($row['share_with']) && $row['share_with'] != '') {
+				$row['share_with_displayname'] = \OCP\User::getDisplayName($row['share_with']);
+			}
+			if ( isset($row['uid_owner']) && $row['uid_owner'] != '') {
+				$row['displayname_owner'] = \OCP\User::getDisplayName($row['uid_owner']);
+			}
+			
 			$items[$row['id']] = $row;
 		}
 		if (!empty($items)) {
diff --git a/lib/public/user.php b/lib/public/user.php
index 204d8e4c0f..de52055a4c 100644
--- a/lib/public/user.php
+++ b/lib/public/user.php
@@ -51,7 +51,25 @@ class User {
 	public static function getUsers($search = '', $limit = null, $offset = null) {
 		return \OC_USER::getUsers();
 	}
-
+	
+	/**
+	 * @brief get the user display name of the user currently logged in.
+	 * @return string display name
+	 */
+	public static function getDisplayName($user=null) {
+		return \OC_USER::getDisplayName($user);
+	}
+	
+	/**
+	 * @brief Get a list of all display names
+	 * @returns array with all display names (value) and the correspondig uids (key)
+	 *
+	 * Get a list of all display names and user ids.
+	 */
+	public static function getDisplayNames($search = '', $limit = null, $offset = null) {
+		return \OC_USER::getDisplayNames($search, $limit, $offset);
+	}
+	
 	/**
 	 * @brief Check if the user is logged in
 	 * @returns true/false
diff --git a/lib/user.php b/lib/user.php
index 85240ce6b6..38259bceea 100644
--- a/lib/user.php
+++ b/lib/user.php
@@ -251,6 +251,7 @@ class OC_User {
 			if($uid && $enabled) {
 				session_regenerate_id(true);
 				self::setUserId($uid);
+				self::setDisplayName($uid);
 				OC_Hook::emit( "OC_User", "post_login", array( "uid" => $uid, 'password'=>$password ));
 				return true;
 			}
@@ -265,6 +266,48 @@ class OC_User {
 		$_SESSION['user_id'] = $uid;
 	}
 
+	/**
+	 * @brief Sets user display name for session
+	 */
+	public static function setDisplayName($uid, $displayName = null) {
+		$result = false;
+		if ($displayName ) {
+			foreach(self::$_usedBackends as $backend) {
+				if($backend->implementsActions(OC_USER_BACKEND_SET_DISPLAYNAME)) {
+					if($backend->userExists($uid)) {
+						$success |= $backend->setDisplayName($uid, $displayName);
+					}
+				}
+			}
+		} else {
+			$displayName = self::determineDisplayName($uid);
+			$result = true;
+		}
+		if (OC_User::getUser() === $uid) {
+			$_SESSION['display_name'] = $displayName;
+		}
+		return $result;
+	}
+
+
+	/**
+	 * @brief get display name
+	 * @param $uid The username
+	 * @returns string display name or uid if no display name is defined
+	 *
+	 */
+	private static function determineDisplayName( $uid ) {
+		foreach(self::$_usedBackends as $backend) {
+			if($backend->implementsActions(OC_USER_BACKEND_GET_DISPLAYNAME)) {
+				$result=$backend->getDisplayName( $uid );
+				if($result) {
+					return $result;
+				}
+			}
+		}
+		return $uid;
+	}
+
 	/**
 	 * @brief Logs the current user out and kills all the session data
 	 *
@@ -320,6 +363,21 @@ class OC_User {
 		}
 	}
 
+	/**
+	 * @brief get the display name of the user currently logged in.
+	 * @return string uid or false
+	 */
+	public static function getDisplayName($user=null) {
+		if ( $user ) {
+			return self::determineDisplayName($user);
+		} else if( isset($_SESSION['display_name']) AND $_SESSION['display_name'] ) {
+			return $_SESSION['display_name'];
+		}
+		else{
+			return false;
+		}
+	}
+
 	/**
 	 * @brief Autogenerate a password
 	 * @returns string
@@ -419,6 +477,24 @@ class OC_User {
 		return $users;
 	}
 
+	/**
+	 * @brief Get a list of all users display name
+	 * @returns associative array with all display names (value) and corresponding uids (key)
+	 *
+	 * Get a list of all display names and user ids.
+	 */
+	public static function getDisplayNames($search = '', $limit = null, $offset = null) {
+		$displayNames = array();
+		foreach (self::$_usedBackends as $backend) {
+			$backendDisplayNames = $backend->getDisplayNames($search, $limit, $offset);
+			if (is_array($backendDisplayNames)) {
+				$displayNames = array_merge($displayNames, $backendDisplayNames);
+			}
+		}
+		ksort($displayNames);
+		return $displayNames;
+	}
+
 	/**
 	 * @brief check if a user exists
 	 * @param string $uid the username
diff --git a/lib/user/backend.php b/lib/user/backend.php
index 2a95db9369..56fa319597 100644
--- a/lib/user/backend.php
+++ b/lib/user/backend.php
@@ -35,6 +35,8 @@ define('OC_USER_BACKEND_CREATE_USER',       0x000001);
 define('OC_USER_BACKEND_SET_PASSWORD',      0x000010);
 define('OC_USER_BACKEND_CHECK_PASSWORD',    0x000100);
 define('OC_USER_BACKEND_GET_HOME',			0x001000);
+define('OC_USER_BACKEND_GET_DISPLAYNAME',	0x010000);
+define('OC_USER_BACKEND_SET_DISPLAYNAME',	0x010000);
 
 
 /**
@@ -50,6 +52,8 @@ abstract class OC_User_Backend implements OC_User_Interface {
 		OC_USER_BACKEND_SET_PASSWORD => 'setPassword',
 		OC_USER_BACKEND_CHECK_PASSWORD => 'checkPassword',
 		OC_USER_BACKEND_GET_HOME => 'getHome',
+		OC_USER_BACKEND_GET_DISPLAYNAME => 'getDisplayName',
+		OC_USER_BACKEND_SET_DISPLAYNAME => 'setDisplayName',
 	);
 
 	/**
@@ -120,4 +124,28 @@ abstract class OC_User_Backend implements OC_User_Interface {
 	public function getHome($uid) {
 		return false;
 	}
+	
+	/**
+	 * @brief get display name of the user
+	 * @param $uid user ID of the user
+	 * @return display name
+	 */
+	public function getDisplayName($uid) {
+		return $uid;
+	}
+	
+	/**
+	 * @brief Get a list of all display names
+	 * @returns array with  all displayNames (value) and the correspondig uids (key)
+	 *
+	 * Get a list of all display names and user ids.
+	 */
+	public function getDisplayNames($search = '', $limit = null, $offset = null) {
+		$displayNames = array();
+		$users = $this->getUsers($search, $limit, $offset);
+		foreach ( $users as $user) {
+			$displayNames[$user] = $user;
+		}
+		return $displayNames;
+	}
 }
diff --git a/lib/user/database.php b/lib/user/database.php
index f33e338e2e..7deeb0c469 100644
--- a/lib/user/database.php
+++ b/lib/user/database.php
@@ -110,7 +110,61 @@ class OC_User_Database extends OC_User_Backend {
 			return false;
 		}
 	}
+	
+	/**
+	 * @brief Set display name
+	 * @param $uid The username
+	 * @param $displayName The new display name
+	 * @returns true/false
+	 *
+	 * Change the display name of a user
+	 */
+	public function setDisplayName( $uid, $displayName ) {
+		if( $this->userExists($uid) ) {
+			$query = OC_DB::prepare( 'UPDATE `*PREFIX*users` SET `displayname` = ? WHERE `uid` = ?' );
+			$query->execute( array( $displayName, $uid ));
+			return true;
+		}else{
+			return false;
+		}
+	}
 
+	/**
+	 * @brief get display name of the user
+	 * @param $uid user ID of the user
+	 * @return display name
+	 */
+	public function getDisplayName($uid) {
+		if( $this->userExists($uid) ) {
+			$query = OC_DB::prepare( 'SELECT displayname FROM `*PREFIX*users` WHERE `uid` = ?' );
+			$result = $query->execute( array( $uid ))->fetchAll();
+			$displayName = trim($result[0]['displayname'], ' ');
+			if ( !empty($displayName) ) {
+				return $displayName;
+			} else {
+				return $uid;
+			}
+		}
+	}
+	
+	/**
+	 * @brief Get a list of all display names
+	 * @returns array with  all displayNames (value) and the correspondig uids (key)
+	 *
+	 * Get a list of all display names and user ids.
+	 */
+	public function getDisplayNames($search = '', $limit = null, $offset = null) {
+		$displayNames = array();
+		$query = OC_DB::prepare('SELECT `uid`, `displayname` FROM `*PREFIX*users` WHERE LOWER(`displayname`) LIKE LOWER(?)', $limit, $offset);
+		$result = $query->execute(array($search.'%'));
+		$users = array();
+		while ($row = $result->fetchRow()) {
+			$displayName =  trim($row['displayname'], ' ');
+			$displayNames[$row['uid']] = empty($displayName) ? $row['uid'] : $displayName;
+		}
+		return $displayNames;
+	}
+	
 	/**
 	 * @brief Check if the password is correct
 	 * @param $uid The username
diff --git a/lib/user/interface.php b/lib/user/interface.php
index 3d9f4691f2..b4667633b5 100644
--- a/lib/user/interface.php
+++ b/lib/user/interface.php
@@ -57,4 +57,19 @@ interface OC_User_Interface {
 	*/
 	public function userExists($uid);
 
+	/**
+	 * @brief get display name of the user
+	 * @param $uid user ID of the user
+	 * @return display name
+	 */
+	public function getDisplayName($uid);
+
+	/**
+	 * @brief Get a list of all display names
+	 * @returns array with  all displayNames (value) and the correspondig uids (key)
+	 *
+	 * Get a list of all display names and user ids.
+	 */
+	public function getDisplayNames($search = '', $limit = null, $offset = null);
+
 }
\ No newline at end of file
diff --git a/lib/util.php b/lib/util.php
index 374baa43db..0543df979d 100755
--- a/lib/util.php
+++ b/lib/util.php
@@ -95,7 +95,7 @@ class OC_Util {
 	 */
 	public static function getVersion() {
 		// hint: We only can count up. So the internal version number of ownCloud 4.5 will be 4.90.0. This is not visible to the user
-		return array(4, 91, 02);
+		return array(4, 91, 03);
 	}
 
 	/**
diff --git a/settings/ajax/changedisplayname.php b/settings/ajax/changedisplayname.php
new file mode 100644
index 0000000000..f80ecb7a0c
--- /dev/null
+++ b/settings/ajax/changedisplayname.php
@@ -0,0 +1,28 @@
+<?php
+// Check if we are a user
+OCP\JSON::callCheck();
+OC_JSON::checkLoggedIn();
+
+$username = isset($_POST["username"]) ? $_POST["username"] : OC_User::getUser();
+$displayName = $_POST["displayName"];
+
+$userstatus = null;
+if(OC_User::isAdminUser(OC_User::getUser())) {
+	$userstatus = 'admin';
+}
+if(OC_SubAdmin::isUserAccessible(OC_User::getUser(), $username)) {
+	$userstatus = 'subadmin';
+}
+
+if(is_null($userstatus)) {
+	OC_JSON::error( array( "data" => array( "message" => "Authentication error" )));
+	exit();
+}
+
+// Return Success story
+if( OC_User::setDisplayName( $username, $displayName )) {
+	OC_JSON::success(array("data" => array( "username" => $username )));
+}
+else{
+	OC_JSON::error(array("data" => array( "message" => "Unable to change display name" )));
+}
\ No newline at end of file
diff --git a/settings/js/users.js b/settings/js/users.js
index 9f0c1ffd11..424d00b51a 100644
--- a/settings/js/users.js
+++ b/settings/js/users.js
@@ -69,7 +69,9 @@ var UserList = {
     add:function (username, groups, subadmin, quota, sort) {
         var tr = $('tbody tr').first().clone();
         tr.attr('data-uid', username);
+        tr.attr('data-displayName', username);
         tr.find('td.name').text(username);
+        tr.find('td.displayName').text(username);
         var groupsSelect = $('<select multiple="multiple" class="groupsselect" data-placehoder="Groups" title="' + t('settings', 'Groups') + '"></select>').attr('data-username', username).attr('data-user-groups', groups);
         tr.find('td.groups').empty();
         if (tr.find('td.subadmins').length > 0) {
@@ -299,6 +301,40 @@ $(document).ready(function () {
     $('td.password').live('click', function (event) {
         $(this).children('img').click();
     });
+    
+    $('td.displayName>img').live('click', function (event) {
+        event.stopPropagation();
+        var img = $(this);
+        var uid = img.parent().parent().attr('data-uid');
+        var displayName = img.parent().parent().attr('data-displayName');
+        var input = $('<input type="text" value="'+displayName+'">');
+        img.css('display', 'none');
+        img.parent().children('span').replaceWith(input);
+        input.focus();
+        input.keypress(function (event) {
+            if (event.keyCode == 13) {
+                if ($(this).val().length > 0) {
+                    $.post(
+                        OC.filePath('settings', 'ajax', 'changedisplayname.php'),
+                        {username:uid, displayName:$(this).val()},
+                        function (result) {
+                        }
+                    );
+                    input.blur();
+                } else {
+                    input.blur();
+                }
+            }
+        });
+        input.blur(function () {
+            $(this).replaceWith($(this).val());
+            img.css('display', '');
+        });
+    });
+    $('td.displayName').live('click', function (event) {
+        $(this).children('img').click();
+    });
+    
 
     $('select.quota, select.quota-user').live('change', function () {
         var select = $(this);
diff --git a/settings/routes.php b/settings/routes.php
index 1c766837dd..0a5b2fbfd3 100644
--- a/settings/routes.php
+++ b/settings/routes.php
@@ -39,6 +39,8 @@ $this->create('settings_ajax_removegroup', '/settings/ajax/removegroup.php')
 	->actionInclude('settings/ajax/removegroup.php');
 $this->create('settings_ajax_changepassword', '/settings/ajax/changepassword.php')
 	->actionInclude('settings/ajax/changepassword.php');
+$this->create('settings_ajax_changedisplayname', '/settings/ajax/changedisplayname.php')
+->actionInclude('settings/ajax/changedisplayname.php');
 // personel
 $this->create('settings_ajax_lostpassword', '/settings/ajax/lostpassword.php')
 	->actionInclude('settings/ajax/lostpassword.php');
diff --git a/settings/templates/users.php b/settings/templates/users.php
index c88966f713..f30c21efae 100644
--- a/settings/templates/users.php
+++ b/settings/templates/users.php
@@ -18,7 +18,7 @@ $_['subadmingroups'] = array_flip($items);
 
 <div id="controls">
 	<form id="newuser" autocomplete="off">
-		<input id="newusername" type="text" placeholder="<?php echo $l->t('Name')?>" /> <input
+		<input id="newusername" type="text" placeholder="<?php echo $l->t('Login Name')?>" /> <input
 			type="password" id="newuserpassword"
 			placeholder="<?php echo $l->t('Password')?>" /> <select
 			class="groupsselect"
@@ -76,7 +76,8 @@ $_['subadmingroups'] = array_flip($items);
 <table data-groups="<?php echo implode(', ', $allGroups);?>">
 	<thead>
 		<tr>
-			<th id='headerName'><?php echo $l->t('Name')?></th>
+			<th id='headerName'><?php echo $l->t('Login Name')?></th>
+			<th id="headerDisplayName"><?php echo $l->t( 'Display Name' ); ?></th>
 			<th id="headerPassword"><?php echo $l->t( 'Password' ); ?></th>
 			<th id="headerGroups"><?php echo $l->t( 'Groups' ); ?></th>
 			<?php if(is_array($_['subadmins']) || $_['subadmins']): ?>
@@ -88,8 +89,13 @@ $_['subadmingroups'] = array_flip($items);
 	</thead>
 	<tbody>
 		<?php foreach($_["users"] as $user): ?>
-		<tr data-uid="<?php echo $user["name"] ?>">
+		<tr data-uid="<?php echo $user["name"] ?>"
+			data-displayName="<?php echo $user["displayName"] ?>">
 			<td class="name"><?php echo $user["name"]; ?></td>
+			<td class="displayName"><span><?php echo $user["displayName"]; ?></span> <img class="svg action"
+				src="<?php echo image_path('core', 'actions/rename.svg')?>"
+				alt="change display name" title="change display name"/>
+			</td>
 			<td class="password"><span>●●●●●●●</span> <img class="svg action"
 				src="<?php echo image_path('core', 'actions/rename.svg')?>"
 				alt="set new password" title="set new password"/>
diff --git a/settings/users.php b/settings/users.php
index 668d974693..ab7a7aed73 100644
--- a/settings/users.php
+++ b/settings/users.php
@@ -22,11 +22,11 @@ $isadmin = OC_User::isAdminUser(OC_User::getUser());
 
 if($isadmin) {
 	$accessiblegroups = OC_Group::getGroups();
-	$accessibleusers = OC_User::getUsers('', 30);
+	$accessibleusers = OC_User::getDisplayNames('', 30);
 	$subadmins = OC_SubAdmin::getAllSubAdmins();
 }else{
 	$accessiblegroups = OC_SubAdmin::getSubAdminsGroups(OC_User::getUser());
-	$accessibleusers = OC_Group::usersInGroups($accessiblegroups, '', 30);
+	$accessibleusers = OC_Group::displayNamesInGroups($accessiblegroups, '', 30);
 	$subadmins = false;
 }
 
@@ -42,16 +42,22 @@ $defaultQuota=OC_Appconfig::getValue('files', 'default_quota', 'none');
 $defaultQuotaIsUserDefined=array_search($defaultQuota, $quotaPreset)===false && array_search($defaultQuota, array('none', 'default'))===false;
 
 // load users and quota
-foreach($accessibleusers as $i) {
-	$quota=OC_Preferences::getValue($i, 'files', 'quota', 'default');
+foreach($accessibleusers as $uid => $displayName) {
+	$quota=OC_Preferences::getValue($uid, 'files', 'quota', 'default');
 	$isQuotaUserDefined=array_search($quota, $quotaPreset)===false && array_search($quota, array('none', 'default'))===false;
 
+	$name = $displayName;
+	if ( $displayName != $uid ) {
+		$name = $name . ' ('.$uid.')';
+	} 
+	
 	$users[] = array(
-		"name" => $i,
-		"groups" => join( ", ", /*array_intersect(*/OC_Group::getUserGroups($i)/*, OC_SubAdmin::getSubAdminsGroups(OC_User::getUser()))*/),
+		"name" => $uid,
+		"displayName" => $displayName, 
+		"groups" => join( ", ", /*array_intersect(*/OC_Group::getUserGroups($uid)/*, OC_SubAdmin::getSubAdminsGroups(OC_User::getUser()))*/),
 		'quota'=>$quota,
 		'isQuotaUserDefined'=>$isQuotaUserDefined,
-		'subadmin'=>implode(', ', OC_SubAdmin::getSubAdminsGroups($i)));
+		'subadmin'=>implode(', ', OC_SubAdmin::getSubAdminsGroups($uid)));
 }
 
 foreach( $accessiblegroups as $i ) {