diff --git a/docs/creating-plugins.md b/docs/creating-plugins.md
index 47b82225..6b0e110b 100644
--- a/docs/creating-plugins.md
+++ b/docs/creating-plugins.md
@@ -17,7 +17,7 @@ As of SystemJS 0.20, instantiation plugins are modules with a `load` method reso
 
 plugin.js
 ```javascript
-export function load (key) {
+export function load (url) {
   return Promise.resolve({
     some: 'value'
   });
@@ -35,7 +35,15 @@ Within this hook, plugins can fetch `key` as a source text, or do any other cust
 is provided, an empty module is used for the plugin module value.
 
 Within the `load` hook `this` is set to the loader itself. It is also possible to call `loader.register(key, deps, declare)` to instantiate the module
-in the plugin load hook.
+in the plugin load hook. Because plugins are referenced via syntax (`resource!plugin`) it is necessary to use the corresponding `registerKey` argument here:
+
+```javascript
+export function load (url, registerKey) {
+  this.register(registerKey, deps, function (_export, _context) {
+    // ... System.register format ...
+  });
+}
+```
 
 > For SystemJS 0.19 and below, instantiation plugins must use the `instantiate` hook API form from the compiler plugins section below.
 
@@ -45,11 +53,11 @@ A CSS loading plugin can be written:
 
 css.js:
 ```javascript
-exports.load = function(key) {
+exports.load = function (url) {
   return new Promise(function (resolve, reject) {
     var link = document.createElement('link');
     link.rel = 'stylesheet';
-    link.href = key;
+    link.href = url;
     link.onload = resolve;
 
     document.head.appendChild(link);
diff --git a/src/instantiate.js b/src/instantiate.js
index 59dcdca1..b86f2c8c 100644
--- a/src/instantiate.js
+++ b/src/instantiate.js
@@ -42,7 +42,7 @@ export function instantiate (key, metadata, processAnonRegister) {
       .then(function () {
         // modern plugin = load hook
         if (metadata.pluginModule && typeof metadata.pluginModule.load === 'function')
-          return runPluginLoad(loader, key, metadata, metadata.pluginKey, metadata.pluginModule);
+          return runPluginLoad(loader, metadata.pluginArgument, key, metadata, metadata.pluginKey, metadata.pluginModule);
         return runFetchPipeline(loader, key, metadata, processAnonRegister, config.wasm);
       })
 
@@ -95,10 +95,10 @@ function protectedCreateNamespace (bindings) {
   return new ModuleNamespace(bindings);
 }
 
-function runPluginLoad (loader, key, metadata, pluginKey, pluginModule) {
+function runPluginLoad (loader, key, registerKey, metadata, pluginKey, pluginModule) {
   return Promise.resolve()
   .then(function () {
-    return pluginModule.load.call(loader, key);
+    return pluginModule.load.call(loader, key, registerKey);
   })
   .then(function (pluginResult) {
     if (pluginResult === undefined)
@@ -501,7 +501,7 @@ function transpile (loader, source, key, metadata) {
   return loader.import.call(loader, loader.transpiler)
   .then(function (transpiler) {
     if (typeof transpiler.load === 'function')
-      return runPluginLoad(loader, key, metadata, loader.transpiler, transpiler);
+      return runPluginLoad(loader, key, key, metadata, loader.transpiler, transpiler);
 
     if (transpiler.__useDefault)
       transpiler = transpiler.default;
diff --git a/test/test.js b/test/test.js
index 9b4b5164..990fcffe 100644
--- a/test/test.js
+++ b/test/test.js
@@ -530,8 +530,8 @@ suite('SystemJS Standard Tests', function() {
 
   test('Instantiate plugin register', function () {
     System.set('instantiate-plugin-register', System.newModule({
-      load: function (key) {
-        this.register(key, [], function (_export) {
+      load: function (key, fullKey) {
+        this.register(fullKey, [], function (_export) {
           return function () {
             _export('some', 'thing');
           };