diff --git a/core/Config.php b/core/Config.php
index 65012f2a9..365875479 100644
--- a/core/Config.php
+++ b/core/Config.php
@@ -310,7 +310,6 @@ class Config {
 	}
 
 	public static function merge_high_into_low(&$result, $value) {
-		if (!$value) return;
 		$newType = self::get_value_type($value);
 
 		if (!$result) {
@@ -509,7 +508,7 @@ class Config {
 	 * Update a configuration value
 	 *
 	 * Configuration is modify only. The value passed is merged into the existing configuration. If you want to
-	 * replace the current value, you'll need to call remove first.
+	 * replace the current array value, you'll need to call remove first.
 	 *
 	 * @param $class string - The class to update a configuration value for
 	 * @param $name string - The configuration property name to update
@@ -522,10 +521,17 @@ class Config {
 	 * You will get an error if you try and override array values with non-array values or vice-versa
 	 */
 	public function update($class, $name, $val) {
-		if (!isset($this->overrides[0][$class])) $this->overrides[0][$class] = array();
+		if(is_null($val)) {
+			$this->remove($class, $name);
+		} else {
+			if (!isset($this->overrides[0][$class])) $this->overrides[0][$class] = array();
 
-		if (!isset($this->overrides[0][$class][$name])) $this->overrides[0][$class][$name] = $val;
-		else self::merge_high_into_low($this->overrides[0][$class][$name], $val);
+			if (!array_key_exists($name, $this->overrides[0][$class])) {
+				$this->overrides[0][$class][$name] = $val;
+			} else {
+				self::merge_high_into_low($this->overrides[0][$class][$name], $val);
+			}
+		}
 
 		$this->cache->clean("__{$class}__{$name}");
 	}
@@ -560,7 +566,7 @@ class Config {
 	 *
 	 * Matching is always by "==", not by "==="
 	 */
-	public function remove($class, $name) {
+	public function remove($class, $name /*,$key = null*/ /*,$value = null*/) {
 		$argc = func_num_args();
 		$key = $argc > 2 ? func_get_arg(2) : self::anything();
 		$value = $argc > 3 ? func_get_arg(3) : self::anything();
diff --git a/tests/core/ConfigTest.php b/tests/core/ConfigTest.php
index 7ed19ed9e..6a2519d69 100644
--- a/tests/core/ConfigTest.php
+++ b/tests/core/ConfigTest.php
@@ -21,6 +21,16 @@ class ConfigStaticTest_First extends Config {
 	public static $first  = array('test_1');
 	public static $second = array('test_1');
 	public static $third  = 'test_1';
+
+	public static $bool = true;
+	public static $int = 42;
+	public static $string = 'value';
+	public static $nullable = 'value';
+
+	public static $default_false = false;
+	public static $default_null = null;
+	public static $default_zero = 0;
+	public static $default_emtpy_string = '';
 }
 
 class ConfigStaticTest_Second extends ConfigStaticTest_First {
@@ -83,6 +93,44 @@ class ConfigTest extends SapphireTest {
 			array('test_3_2'));
 	}
 
+	public function testUpdateWithFalsyValues() {
+		// Booleans
+		$this->assertTrue(Config::inst()->get('ConfigStaticTest_First', 'bool'));
+		Config::inst()->update('ConfigStaticTest_First', 'bool', false);
+		$this->assertFalse(Config::inst()->get('ConfigStaticTest_First', 'bool'));
+		Config::inst()->update('ConfigStaticTest_First', 'bool', true);
+		$this->assertTrue(Config::inst()->get('ConfigStaticTest_First', 'bool'));
+
+		// Integers
+		$this->assertEquals(42, Config::inst()->get('ConfigStaticTest_First', 'int'));
+		Config::inst()->update('ConfigStaticTest_First', 'int', 0);
+		$this->assertEquals(0, Config::inst()->get('ConfigStaticTest_First', 'int'));
+		Config::inst()->update('ConfigStaticTest_First', 'int', 42);
+		$this->assertEquals(42, Config::inst()->get('ConfigStaticTest_First', 'int'));
+
+		// Strings
+		$this->assertEquals('value', Config::inst()->get('ConfigStaticTest_First', 'string'));
+		Config::inst()->update('ConfigStaticTest_First', 'string', '');
+		$this->assertEquals('', Config::inst()->get('ConfigStaticTest_First', 'string'));
+		Config::inst()->update('ConfigStaticTest_First', 'string', 'value');
+		$this->assertEquals('value', Config::inst()->get('ConfigStaticTest_First', 'string'));
+
+		// Nulls
+		$this->assertEquals('value', Config::inst()->get('ConfigStaticTest_First', 'nullable'));
+		Config::inst()->update('ConfigStaticTest_First', 'nullable', null);
+		$this->assertNull(Config::inst()->get('ConfigStaticTest_First', 'nullable'));
+		Config::inst()->update('ConfigStaticTest_First', 'nullable', 'value');
+		$this->assertEquals('value', Config::inst()->get('ConfigStaticTest_First', 'nullable'));
+	}
+
+	public function testSetsFalsyDefaults() {
+		$this->assertFalse(Config::inst()->get('ConfigStaticTest_First', 'default_false'));
+		// Technically the same as an undefined config key
+		$this->assertNull(Config::inst()->get('ConfigStaticTest_First', 'default_null'));
+		$this->assertEquals(0, Config::inst()->get('ConfigStaticTest_First', 'default_zero'));
+		$this->assertEquals('', Config::inst()->get('ConfigStaticTest_First', 'default_empty_string'));
+	}
+
 	public function testUninheritedStatic() {
 		$this->assertEquals(Config::inst()->get('ConfigStaticTest_First',  'third', Config::UNINHERITED), 'test_1');
 		$this->assertEquals(Config::inst()->get('ConfigStaticTest_Fourth', 'third', Config::UNINHERITED), null);