diff --git a/Dice.php b/Dice.php
index b75299b..be87773 100644
--- a/Dice.php
+++ b/Dice.php
@@ -55,8 +55,8 @@ private function addRuleTo(Dice $dice, string $name, array $rule) {
         if (isset($rule['substitutions'])) foreach($rule['substitutions'] as $key => $value) $rule['substitutions'][ltrim($key,  '\\')] = $value;
         //Clear any existing instance or cache for this class
         unset($dice->instances[$name], $dice->cache[$name]);
-        $dice->rules[ltrim(strtolower($name), '\\')] = array_replace_recursive($dice->getRule($name), $rule);
-    }
+		$dice->rules[ltrim(strtolower($name), '\\')] = array_replace_recursive($dice->getRule($name), $rule);
+	}
 
 	/**
 	 * Returns the rule that will be applied to the class $name when calling create()
@@ -65,7 +65,7 @@ private function addRuleTo(Dice $dice, string $name, array $rule) {
 	 */
 	public function getRule(string $name): array {
 		$lcName = strtolower(ltrim($name, '\\'));
-		if (isset($this->rules[$lcName])) return $this->rules[$lcName];
+		if (isset($this->rules[$lcName])) return $this->appendGlobalRule($lcName, $this->rules[$lcName]);
 
 		foreach ($this->rules as $key => $rule) { 							// Find a rule which matches the class described in $name where:
 			if (empty($rule['instanceOf']) 		 							// It's not a named instance, the rule is applied to a class name
@@ -78,6 +78,18 @@ public function getRule(string $name): array {
 		return isset($this->rules['*']) ? $this->rules['*'] : [];
 	}
 
+	private function appendGlobalRule(string $name, array $rules) : array
+	{
+		if ($name === '*') return $rules;
+
+		$globalRules = isset($this->rules['*']) ? $this->rules['*'] : [];
+		if (!isset($globalRules['substitutions'])) return $rules;
+
+		$subs = isset($rules['substitutions']) ? $rules['substitutions'] : [];
+		$rules['substitutions'] = array_merge($globalRules['substitutions'], $subs);
+		return $rules;
+	}
+
 	/**
 	 * Returns a fully constructed object based on $name using $args and $share as constructor arguments if supplied
 	 * @param string name The name of the class to instantiate
@@ -191,8 +203,7 @@ private function expand($param, array $share = [], bool $createFromString = fals
 	}
 	/**
 	* Looks through the array $search for any object which can be used to fulfil $param
-	The original array $search is modifed so must be passed by reference.
-
+	* The original array $search is modifed so must be passed by reference.
 	*/
 	private function matchParam(\ReflectionParameter $param, $class, array &$search) {
 		foreach ($search as $i => $arg) {
diff --git a/tests/GlobalRuleTest.php b/tests/GlobalRuleTest.php
new file mode 100644
index 0000000..0aafd2c
--- /dev/null
+++ b/tests/GlobalRuleTest.php
@@ -0,0 +1,164 @@
+<?php
+/* @description Dice - A minimal Dependency Injection Container for PHP *
+ * @author Tom Butler tom@r.je *
+ * @copyright 2012-2018 Tom Butler <tom@r.je> | https:// r.je/dice.html *
+ * @license http:// www.opensource.org/licenses/bsd-license.php BSD License *
+ * @version 3.0 */
+class GlobalRuleTest extends DiceTest
+{
+    public function testGlobal1()
+    {
+		$rule = [
+			'substitutions' => ['GlobalInterface' => 'GlobalImplementation']
+		];
+		$dice = $this->dice->addRule('*', $rule);
+
+		$obj = $dice->create('Global1');
+
+		$this->assertInstanceOf('GlobalImplementation', $obj->obj);
+    }
+
+    public function testGlobal2()
+    {
+		$rule = [
+			'substitutions' => ['GlobalInterface' => 'GlobalImplementation']
+		];
+		$dice = $this->dice->addRule('*', $rule);
+
+		$obj = $dice->create('Global2');
+
+		$this->assertInstanceOf('GlobalImplementation', $obj->obj);
+    }
+
+    public function testGlobal3()
+    {
+		$rule = [
+			'substitutions' => ['GlobalInterface' => 'GlobalImplementation']
+		];
+		$dice = $this->dice->addRule('*', $rule);
+
+		$obj = $dice->create('Global3');
+
+		$this->assertInstanceOf('GlobalImplementation', $obj->obj);
+    }
+
+    public function testGlobal4()
+    {
+		$rule = [
+            'substitutions' => [
+                'GlobalRuleInterface' => 'GlobalRuleImplementation',
+                'GlobalInterface' => 'GlobalImplementation'
+            ]
+		];
+		$dice = $this->dice->addRule('*', $rule);
+
+		$obj = $dice->create('Global4');
+
+        $this->assertInstanceOf('GlobalImplementation', $obj->glb);
+        $this->assertInstanceOf('GlobalRuleImplementation', $obj->glbr);
+    }
+
+    public function testGlobal4_1()
+    {
+		$glbRule = [
+            'substitutions' => ['GlobalInterface' => 'GlobalImplementation']
+        ];
+        $glb4Rule = [
+            'substitutions' => ['GlobalRuleInterface' => 'GlobalRuleImplementation']
+		];
+		$dice = $this->dice->addRule('*', $glbRule);
+        $dice = $dice->addRule('Global4', $glb4Rule);
+
+		$obj = $dice->create('Global4');
+
+        $this->assertInstanceOf('GlobalImplementation', $obj->glb);
+        $this->assertInstanceOf('GlobalRuleImplementation', $obj->glbr);
+    }
+
+    public function testGlobal4_2()
+    {
+		$glbRule = [
+            'substitutions' => ['GlobalRuleInterface' => 'GlobalRuleImplementation']
+        ];
+        $glb4Rule = [
+            'substitutions' => ['GlobalInterface' => 'GlobalImplementation']
+		];
+		$dice = $this->dice->addRule('*', $glbRule);
+        $dice = $dice->addRule('Global4', $glb4Rule);
+
+		$obj = $dice->create('Global4');
+
+        $this->assertInstanceOf('GlobalImplementation', $obj->glb);
+        $this->assertInstanceOf('GlobalRuleImplementation', $obj->glbr);
+    }
+
+    public function testGlobal4_3()
+    {
+		$glbRule = [
+            'substitutions' => ['GlobalInterface' => 'GlobalImplementation']
+        ];
+        $glb4Rule = [
+            'substitutions' => [
+                'GlobalInterface' => 'AnotherGlobalImplementation',
+                'GlobalRuleInterface' => 'GlobalRuleImplementation'
+            ]
+		];
+		$dice = $this->dice->addRule('*', $glbRule);
+        $dice = $dice->addRule('Global4', $glb4Rule);
+
+		$obj = $dice->create('Global4');
+
+        $this->assertInstanceOf('AnotherGlobalImplementation', $obj->glb);
+        $this->assertInstanceOf('GlobalRuleImplementation', $obj->glbr);
+    }
+
+    public function testGlobal4_4()
+    {
+		$glbRule = [
+            'substitutions' => ['GlobalRuleInterface' => 'GlobalRuleImplementation']
+        ];
+        $glb4Rule = [
+            'substitutions' => ['GlobalInterface' => 'GlobalImplementation']
+		];
+        $dice = $this->dice->addRule('Global4', $glb4Rule);
+		$dice = $dice->addRule('*', $glbRule);
+
+		$obj = $dice->create('Global4');
+
+        $this->assertInstanceOf('GlobalImplementation', $obj->glb);
+        $this->assertInstanceOf('GlobalRuleImplementation', $obj->glbr);
+    }
+
+    public function testGlobal4_5()
+    {
+		$glbRule = [
+            'substitutions' => ['GlobalInterface' => 'GlobalImplementation']
+        ];
+        $glb4Rule = [
+            'substitutions' => [
+                'GlobalInterface' => 'AnotherGlobalImplementation',
+                'GlobalRuleInterface' => 'GlobalRuleImplementation'
+            ]
+		];
+        $dice = $this->dice->addRule('Global4', $glb4Rule);
+		$dice = $dice->addRule('*', $glbRule);
+
+		$obj = $dice->create('Global4');
+
+        $this->assertInstanceOf('AnotherGlobalImplementation', $obj->glb);
+        $this->assertInstanceOf('GlobalRuleImplementation', $obj->glbr);
+    }
+
+    public function testNoSubstitutionKey()
+    {
+		$rule = [
+			'substitutions' => ['GlobalInterface' => 'GlobalImplementation']
+        ];
+        $dice = $this->dice->addRule('Global3', ['shared'=> true]);
+		$dice = $dice->addRule('*', $rule);
+
+		$obj = $dice->create('Global3');
+
+		$this->assertInstanceOf('GlobalImplementation', $obj->obj);
+    }
+}
diff --git a/tests/TestData/GlobalRule.php b/tests/TestData/GlobalRule.php
new file mode 100644
index 0000000..9c6565a
--- /dev/null
+++ b/tests/TestData/GlobalRule.php
@@ -0,0 +1,68 @@
+<?php
+
+interface GlobalInterface
+{
+
+}
+
+class GlobalImplementation implements GlobalInterface
+{
+
+}
+
+class AnotherGlobalImplementation implements GlobalInterface
+{
+
+}
+
+interface GlobalRuleInterface
+{
+
+}
+
+class GlobalRuleImplementation implements GlobalRuleInterface
+{
+
+}
+
+class Global1
+{
+    public $obj;
+    public function __construct(GlobalInterface $obj)
+    {
+        $this->obj = $obj;
+    }
+}
+
+class Global2
+{
+    public $std;
+    public $obj;
+    public function __construct(stdClass $std, GlobalInterface $obj)
+    {
+        $this->std = $std;
+        $this->obj = $obj;
+    }
+}
+
+class Global3
+{
+    public $obj;
+    public $std;
+    public function __construct(GlobalInterface $obj, stdClass $std)
+    {
+        $this->obj = $obj;
+        $this->std = $std;
+    }
+}
+
+class Global4
+{
+    public $glb;
+    public $glbr;
+    public function __construct(GlobalInterface $glb, GlobalRuleInterface $glbr)
+    {
+        $this->glb = $glb;
+        $this->glbr = $glbr;
+    }
+}