diff --git a/core/model/DataObject.php b/core/model/DataObject.php
index e518a87f2..5394b2b61 100644
--- a/core/model/DataObject.php
+++ b/core/model/DataObject.php
@@ -392,18 +392,41 @@ class DataObject extends ViewableData implements DataObjectInterface {
 	}
 
 	/**
-	 * Pass a number of field changes in a map.
-	 * Doesn't write to the database. To write the data,
-	 * use the write() method.
+	 * Update a number of fields on this object, given a map of the desired changes.
+	 * 
+	 * The field names can be simple names, or you can use a dot syntax to access relations.
+	 * For example, array("Author.FirstName" => "Jim") will set $this->Author()->FirstName to "Jim".
+	 * 
+	 * update() doesn't write the main object, but if you use the dot syntax, it will write() 
+	 * the related objects that it alters.
 	 *
 	 * @param array $data A map of field name to data values to update.
 	 */
 	public function update($data) {
 		foreach($data as $k => $v) {
-			$this->$k = $v;
+			// Implement dot syntax for updates
+			if(strpos($k,'.') !== false) {
+				$relations = explode('.', $k);
+				$fieldName = array_pop($relations);
+				$relObj = $this;
+				foreach($relations as $i=>$relation) {
+					$relObj = $relObj->$relation();
+					// If the intermediate relationship objects have been created, then write them
+					if($i<sizeof($relation)-1 && !$relObj->ID) $relObj->write();
+				}
+				if($relObj) {
+					$relObj->$fieldName = $v;
+					$relObj->write();
+					$relObj->flushCache();
+				} else {
+					user_error("Couldn't follow dot syntax '$k' on '$this->class' object", E_USER_WARNING);
+				}
+			} else {
+				$this->$k = $v;
+			}
 		}
 	}
-
+	
 	/**
 	 * Pass changes as a map, and try to
 	 * get automatic casting for these fields.
@@ -1644,7 +1667,6 @@ class DataObject extends ViewableData implements DataObjectInterface {
 			if(!isset($this->record[$fieldName]) || $this->record[$fieldName] !== $val) {
 				// TODO Add check for php-level defaults which are not set in the db
 				// TODO Add check for hidden input-fields (readonly) which are not set in the db
-
 				if(
 					// Main non type-based check
 					(isset($this->record[$fieldName]) && $this->record[$fieldName] != $val)
diff --git a/tests/DataObjectTest.php b/tests/DataObjectTest.php
index c4842452c..6f82feae0 100644
--- a/tests/DataObjectTest.php
+++ b/tests/DataObjectTest.php
@@ -289,6 +289,17 @@ class DataObjectTest extends SapphireTest {
 		$this->assertEquals(0, DB::query("SELECT CaptainID FROM DataObjectTest_Team WHERE ID = $existingTeam->ID")->value());
 	}
 	
+	function testCanAccessHasOneObjectsAsMethods() {
+		/* If you have a has_one relation 'Captain' on $obj, and you set the $obj->CaptainID = (ID), then the object itself should
+		 * be accessible as $obj->Captain() */
+		$team = $this->objFromFixture('DataObjectTest_Team', 'team1');
+		$captainID = $this->idFromFixture('DataObjectTest_Player', 'captain1');
+		
+		$team->CaptainID = $captainID;
+		$this->assertNotNull($team->Captain());
+		$this->assertEquals($captainID, $team->Captain()->ID);
+	}
+	
 	function testFieldNamesThatMatchMethodNamesWork() {
 		/* Check that a field name that corresponds to a method on DataObject will still work */
 		$obj = new DataObjectTest_FunnyFieldNames();
@@ -428,13 +439,42 @@ class DataObjectTest extends SapphireTest {
 			'databaseFields() on subclass contains only fields defined on instance'
 		);
 	}
+	
+	function testDataObjectUpdate() {
+		/* update() calls can use the dot syntax to reference has_one relations and other methods that return objects */
+		$team1 = $this->objFromFixture('DataObjectTest_Team', 'team1');
+		$team1->CaptainID = $this->idFromFixture('DataObjectTest_Player', 'captain1');
+		
+		$team1->update(array(
+			'DatabaseField' => 'Something',
+			'Captain.FirstName' => 'Jim',
+			'Captain.Email' => 'jim@example.com',
+			'Captain.FavouriteTeam.Title' => 'New and improved team 1',
+		));
+		
+		/* Test the simple case of updating fields on the object itself */
+		$this->assertEquals('Something', $team1->DatabaseField);
+
+		/* Setting Captain.Email and Captain.FirstName will have updated DataObjectTest_Captain.captain1 in the database.  Although update()
+		 * doesn't usually write, it does write related records automatically. */
+		$captain1 = $this->objFromFixture('DataObjectTest_Player', 'captain1');
+		$this->assertEquals('Jim', $captain1->FirstName);
+		$this->assertEquals('jim@example.com', $captain1->Email);
+		
+		/* Jim's favourite team is team 1; we need to reload the object to the the change that setting Captain.FavouriteTeam.Title made */
+		$reloadedTeam1 = $this->objFromFixture('DataObjectTest_Team', 'team1');
+		$this->assertEquals('New and improved team 1', $reloadedTeam1->Title);
+	}
 }
 
 class DataObjectTest_Player extends Member implements TestOnly {
-   
-   static $belongs_many_many = array(
-      'Teams' => 'DataObjectTest_Team'
-   );
+	static $has_one = array(
+		'FavouriteTeam' => 'DataObjectTest_Team',
+	);
+
+	static $belongs_many_many = array(
+		'Teams' => 'DataObjectTest_Team'
+	);
    
 }
 
diff --git a/tests/DataObjectTest.yml b/tests/DataObjectTest.yml
index 85d487d8f..c7aa6e058 100644
--- a/tests/DataObjectTest.yml
+++ b/tests/DataObjectTest.yml
@@ -42,6 +42,13 @@ DataObjectTest_Team:
       Title: Team 2
       
 DataObjectTest_Player:
+   captain1:
+      FirstName: Captain 1
+      FavouriteTeam: =>DataObjectTest_Team.team1
+      Teams: =>DataObjectTest_Team.team1
+   captain2:
+      FirstName: Captain 2
+      Teams: =>DataObjectTest_Team.team2
    player1:
       FirstName: Player 1
    player2: