diff --git a/README.md b/README.md
index c95ef5a..86559d9 100644
--- a/README.md
+++ b/README.md
@@ -9,19 +9,31 @@ For the latest stable version:
 ## npm
 
 ```sh
+# TypeScript 2.3.3 or later
 npm install tslib
+
+# TypeScript 2.3.2 or earlier
+npm install tslib@1.6.1
 ```
 
 ## bower
 
 ```sh
+# TypeScript 2.3.3 or later
 bower install tslib
+
+# TypeScript 2.3.2 or earlier
+bower install tslib@1.6.1
 ```
 
 ## JSPM
 
 ```sh
+# TypeScript 2.3.3 or later
 jspm install npm:tslib
+
+# TypeScript 2.3.2 or earlier
+jspm install npm:tslib@1.6.1
 ```
 
 # Usage
@@ -68,7 +80,7 @@ For JSPM users:
         "importHelpers": true,
         "baseUrl": "./",
         "paths": {
-            "tslib" : ["jspm_packages/npm/tslib@1.6.1/tslib.d.ts"]
+            "tslib" : ["jspm_packages/npm/tslib@1.7.0/tslib.d.ts"]
         }
     }
 }
diff --git a/bower.json b/bower.json
index f6f95f7..e3701e8 100644
--- a/bower.json
+++ b/bower.json
@@ -4,7 +4,7 @@
     "Microsoft Corp."
   ],
   "homepage": "http://typescriptlang.org/",
-  "version": "1.6.0",
+  "version": "1.7.0",
   "license": "Apache-2.0",
   "description": "Runtime library for TypeScript helper functions",
   "keywords": [
diff --git a/package.json b/package.json
index d9c1d5f..099660e 100644
--- a/package.json
+++ b/package.json
@@ -2,7 +2,7 @@
     "name": "tslib",
     "author": "Microsoft Corp.",
     "homepage": "http://typescriptlang.org/",
-    "version": "1.6.1",
+    "version": "1.7.0",
     "license": "Apache-2.0",
     "description": "Runtime library for TypeScript helper functions",
     "keywords": [
diff --git a/tslib.d.ts b/tslib.d.ts
index fe466ed..08217ba 100644
--- a/tslib.d.ts
+++ b/tslib.d.ts
@@ -24,6 +24,7 @@ export declare function __exportStar(m: any, exports: any): void;
 export declare function __values(o: any): any;
 export declare function __read(o: any, n?: number): any[];
 export declare function __spread(...args: any[]): any[];
+export declare function __await(v: any): any;
 export declare function __asyncGenerator(thisArg: any, _arguments: any, generator: Function): any;
 export declare function __asyncDelegator(o: any): any;
 export declare function __asyncValues(o: any): any;
\ No newline at end of file
diff --git a/tslib.es6.js b/tslib.es6.js
index c2ce0be..73c4c80 100644
--- a/tslib.es6.js
+++ b/tslib.es6.js
@@ -30,7 +30,7 @@ export var __assign = Object.assign || function __assign(t) {
         for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p)) t[p] = s[p];
     }
     return t;
-};
+}
 
 export function __rest(s, e) {
     var t = {};
@@ -107,7 +107,7 @@ export function __values(o) {
             return { value: o && o[i++], done: !o };
         }
     };
-};
+}
 
 export function __read(o, n) {
     var m = typeof Symbol === "function" && o[Symbol.iterator];
@@ -124,36 +124,38 @@ export function __read(o, n) {
         finally { if (e) throw e.error; }
     }
     return ar;
-};
+}
 
 export function __spread() {
     for (var ar = [], i = 0; i < arguments.length; i++)
         ar = ar.concat(__read(arguments[i]));
     return ar;
-};
+}
+
+export function __await(v) {
+    return this instanceof __await ? (this.v = v, this) : new __await(v);
+}
 
 export function __asyncGenerator(thisArg, _arguments, generator) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
-    var g = generator.apply(thisArg, _arguments || []), q = [], c, i;
-    return i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.asyncIterator] = function () { return this; }, i;
-    function verb(n) { return function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]), next(); }); }; }
-    function next() { if (!c && q.length) resume((c = q.shift())[0], c[1]); }
-    function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(c[3], e); } }
-    function step(r) { r.done ? settle(c[2], r) : Promise.resolve(r.value[1]).then(r.value[0] === "yield" ? send : fulfill, reject); }
-    function send(value) { settle(c[2], { value: value, done: false }); }
+    var g = generator.apply(thisArg, _arguments || []), i, q = [];
+    return i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.asyncIterator] = function () { return this; }, i;
+    function verb(n) { if (g[n]) i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; }
+    function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(q[0][3], e); } }
+    function step(r) { r.value instanceof __await ? Promise.resolve(r.value.v).then(fulfill, reject) : settle(q[0][2], r);  }
     function fulfill(value) { resume("next", value); }
     function reject(value) { resume("throw", value); }
-    function settle(f, v) { c = void 0, f(v), next(); }
-};
+    function settle(f, v) { if (f(v), q.shift(), q.length) resume(q[0][0], q[0][1]); }
+}
 
 export function __asyncDelegator(o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
-};
+    var i, p;
+    return i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { if (o[n]) i[n] = function (v) { return (p = !p) ? { value: __await(o[n](v)), done: n === "return" } : v; }; }
+}
 
 export function __asyncValues(o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
     var m = o[Symbol.asyncIterator];
     return m ? m.call(o) : typeof __values === "function" ? __values(o) : o[Symbol.iterator]();
-};
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/tslib.js b/tslib.js
index 4e4fbcc..850ae26 100644
--- a/tslib.js
+++ b/tslib.js
@@ -25,6 +25,7 @@ var __exportStar;
 var __values;
 var __read;
 var __spread;
+var __await;
 var __asyncGenerator;
 var __asyncDelegator;
 var __asyncValues;
@@ -162,24 +163,26 @@ var __asyncValues;
         return ar;
     };
 
+    __await = function (v) {
+        return this instanceof __await ? (this.v = v, this) : new __await(v);
+    };
+
     __asyncGenerator = function (thisArg, _arguments, generator) {
         if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
-        var g = generator.apply(thisArg, _arguments || []), q = [], c, i;
-        return i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.asyncIterator] = function () { return this; }, i;
-        function verb(n) { return function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]), next(); }); }; }
-        function next() { if (!c && q.length) resume((c = q.shift())[0], c[1]); }
-        function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(c[3], e); } }
-        function step(r) { r.done ? settle(c[2], r) : Promise.resolve(r.value[1]).then(r.value[0] === "yield" ? send : fulfill, reject); }
-        function send(value) { settle(c[2], { value: value, done: false }); }
+        var g = generator.apply(thisArg, _arguments || []), i, q = [];
+        return i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.asyncIterator] = function () { return this; }, i;
+        function verb(n) { if (g[n]) i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; }
+        function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(q[0][3], e); } }
+        function step(r) { r.value instanceof __await ? Promise.resolve(r.value.v).then(fulfill, reject) : settle(q[0][2], r);  }
         function fulfill(value) { resume("next", value); }
         function reject(value) { resume("throw", value); }
-        function settle(f, v) { c = void 0, f(v), next(); }
+        function settle(f, v) { if (f(v), q.shift(), q.length) resume(q[0][0], q[0][1]); }
     };
 
     __asyncDelegator = function (o) {
-        var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-        return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-        function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+        var i, p;
+        return i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.iterator] = function () { return this; }, i;
+        function verb(n) { if (o[n]) i[n] = function (v) { return (p = !p) ? { value: __await(o[n](v)), done: n === "return" } : v; }; }
     };
 
     __asyncValues = function (o) {
@@ -200,6 +203,7 @@ var __asyncValues;
     exporter("__values", __values);
     exporter("__read", __read);
     exporter("__spread", __spread);
+    exporter("__await", __await);
     exporter("__asyncGenerator", __asyncGenerator);
     exporter("__asyncDelegator", __asyncDelegator);
     exporter("__asyncValues", __asyncValues);