diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0bb8ffca..61486ae9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,7 +5,7 @@ Old files can still be opened and files open in read-only mode will not be modif
 * The SyncConfig now gets two more optional parameters, `validate_ssl` and `ssl_trust_certificate_path`.
 
 ### Enhancements
-* None
+* Add Realm open async API support.
 
 ### Bug fixes
 * None
diff --git a/lib/extensions.js b/lib/extensions.js
index 727b910a..999deeb9 100644
--- a/lib/extensions.js
+++ b/lib/extensions.js
@@ -40,6 +40,34 @@ module.exports = function(realmConstructor) {
     setConstructorOnPrototype(realmConstructor.Results);
     setConstructorOnPrototype(realmConstructor.Object);
 
+    //Add async open API
+    Object.defineProperties(realmConstructor, getOwnPropertyDescriptors({
+        open(config) {
+            return new Promise((resolve, reject) => {
+                const realm = new Realm(config);
+                realm.wait((error) => {
+                    if (error) {
+                        reject(new Error("Cannot asynchronously open synced Realm, because the associated session previously experienced a fatal error"));
+                    }
+
+                    resolve(realm);
+                });
+            });
+        },
+
+        openAsync(config, callback) {
+            const realm = new Realm(config);
+            realm.wait((error) => {
+                if (error) {
+                    callback(new Error("Cannot asynchronously open synced Realm, because the associated session previously experienced a fatal error"));
+                    return;
+                }
+
+                callback(null, realm);
+            });
+        }
+    }));
+
     // Add sync methods
     if (realmConstructor.Sync) {
         let userMethods = require('./user-methods');
diff --git a/src/js_realm.hpp b/src/js_realm.hpp
index b96e1eec..f76f5876 100644
--- a/src/js_realm.hpp
+++ b/src/js_realm.hpp
@@ -164,6 +164,8 @@ class RealmClass : public ClassDefinition<T, SharedRealm, ObservableClass<T>> {
 public:
     using ObjectDefaultsMap = typename Schema<T>::ObjectDefaultsMap;
     using ConstructorMap = typename Schema<T>::ConstructorMap;
+    
+    using WaitHandler = void();
 
     static FunctionType create_constructor(ContextType);
 
@@ -175,6 +177,7 @@ public:
     static void delete_all(ContextType, FunctionType, ObjectType, size_t, const ValueType[], ReturnValue &);
     static void write(ContextType, FunctionType, ObjectType, size_t, const ValueType[], ReturnValue &);
     static void add_listener(ContextType, FunctionType, ObjectType, size_t, const ValueType[], ReturnValue &);
+    static void wait_for_download_completion(ContextType, FunctionType, ObjectType, size_t, const ValueType[], ReturnValue &);
     static void remove_listener(ContextType, FunctionType, ObjectType, size_t, const ValueType[], ReturnValue &);
     static void remove_all_listeners(ContextType, FunctionType, ObjectType, size_t, const ValueType[], ReturnValue &);
     static void close(ContextType, FunctionType, ObjectType, size_t, const ValueType[], ReturnValue &);
@@ -220,6 +223,7 @@ public:
         {"deleteAll", wrap<delete_all>},
         {"write", wrap<write>},
         {"addListener", wrap<add_listener>},
+        {"wait", wrap<wait_for_download_completion>},
         {"removeListener", wrap<remove_listener>},
         {"removeAllListeners", wrap<remove_all_listeners>},
         {"close", wrap<close>},
@@ -537,6 +541,40 @@ void RealmClass<T>::get_sync_session(ContextType ctx, ObjectType object, ReturnV
     }
 
 }
+
+template<typename T>
+void RealmClass<T>::wait_for_download_completion(ContextType ctx, FunctionType, ObjectType this_object, size_t argc, const ValueType arguments[], ReturnValue &return_value) {
+    validate_argument_count(argc, 1);
+    auto callback = Value::validated_to_function(ctx, arguments[0]);
+
+    SharedRealm realm = *get_internal<T, RealmClass<T>>(this_object);
+
+    Protected<FunctionType> protected_callback(ctx, callback);
+    Protected<ObjectType> protected_this(ctx, this_object);
+    Protected<typename T::GlobalContext> protected_ctx(Context<T>::get_global_context(ctx));
+
+    EventLoopDispatcher<WaitHandler> wait_handler([=]() {
+        HANDLESCOPE
+        //Function<T>::call(protected_ctx, protected_callback, protected_this, 0, nullptr);
+        Function<T>::callback(protected_ctx, protected_callback, protected_this, 0, nullptr);
+
+        //::node::MakeCallback(context->GetIsolate(), context->Global(), callback, 1, arguments);
+        //::v8::Isolate::GetCurrent()->RunMicrotasks();
+    });
+    std::function<WaitHandler> waitFunc = std::move(wait_handler);
+
+    if (std::shared_ptr<SyncSession> session = SyncManager::shared().get_existing_active_session(realm->config().path)) {
+        session->wait_for_download_completion([=](std::error_code error_code) {
+          waitFunc();
+        });
+       return;
+    }
+   
+   ValueType callback_arguments[1];
+   callback_arguments[0] = Value::from_null(ctx);
+   Function<T>::call(ctx, callback, this_object, 1, callback_arguments);
+}
+
 #endif
 
 template<typename T>
diff --git a/tests/js/session-tests.js b/tests/js/session-tests.js
index c0f88575..46ede801 100644
--- a/tests/js/session-tests.js
+++ b/tests/js/session-tests.js
@@ -50,17 +50,25 @@ module.exports = {
 
     testProperties() {
         return promisifiedRegister('http://localhost:9080', uuid(), 'password').then(user => {
-            return new Promise((resolve, _reject) => {
+            return new Promise((resolve, reject) => {
+                
                 const accessTokenRefreshed = this;
+                let successCounter = 0;
+                function checkSuccess() {
+                    successCounter++;
+                    if (successCounter == 2) {
+                        resolve();
+                    }
+                }
 
                 function postTokenRefreshChecks(sender, error) {
                     try {
                         TestCase.assertEqual(error, accessTokenRefreshed);
                         TestCase.assertEqual(sender.url, `realm://localhost:9080/${user.identity}/myrealm`);
-                        resolve();
+                        checkSuccess();
                     }
                     catch (e) {
-                        _reject(e)
+                        reject(e)
                     }
                 };
 
@@ -70,14 +78,106 @@ module.exports = {
                 const config = { sync: { user, url: 'realm://localhost:9080/~/myrealm', error: postTokenRefreshChecks } };
                 const realm = new Realm(config);
                 const session = realm.syncSession;
-
-
                 TestCase.assertInstanceOf(session, Realm.Sync.Session);
                 TestCase.assertEqual(session.user.identity, user.identity);
                 TestCase.assertEqual(session.config.url, config.sync.url);
                 TestCase.assertEqual(session.config.user.identity, config.sync.user.identity);
                 TestCase.assertUndefined(session.url);
                 TestCase.assertEqual(session.state, 'active');
+                checkSuccess();
+            });
+        });
+    },
+
+    testPropertiesWithOpen() {
+        return promisifiedRegister('http://localhost:9080', uuid(), 'password').then(user => {
+            return new Promise((resolve, reject) => {
+
+                const accessTokenRefreshed = this;
+                let successCounter = 0;
+
+                function checkSuccess() {
+                    successCounter++;
+                    if (successCounter == 2) {
+                        resolve();
+                    }
+                }
+
+                function postTokenRefreshChecks(sender, error) {
+                    try {
+                        TestCase.assertEqual(error, accessTokenRefreshed);
+                        TestCase.assertEqual(sender.url, `realm://localhost:9080/${user.identity}/myrealm`);
+                        checkSuccess();
+                    }
+                    catch (e) {
+                        reject(e)
+                    }
+                };
+
+                // Let the error handler trigger our checks when the access token was refreshed.
+                postTokenRefreshChecks._notifyOnAccessTokenRefreshed = accessTokenRefreshed;
+
+                const config = { sync: { user, url: 'realm://localhost:9080/~/myrealm', error: postTokenRefreshChecks } };
+                Realm.open(config)
+                    .then(realm => {
+                        const session = realm.syncSession;
+                        TestCase.assertInstanceOf(session, Realm.Sync.Session);
+                        TestCase.assertEqual(session.user.identity, user.identity);
+                        TestCase.assertEqual(session.config.url, config.sync.url);
+                        TestCase.assertEqual(session.config.user.identity, config.sync.user.identity);
+                        TestCase.assertEqual(session.state, 'active');
+                        checkSuccess();
+                    })
+                    .catch(e => reject(e));
+            });
+        });
+    },
+
+     
+     testPropertiesWithOpenAsync() {
+        return promisifiedRegister('http://localhost:9080', uuid(), 'password').then(user => {
+            return new Promise((resolve, reject) => {
+                
+                const accessTokenRefreshed = this;
+                let successCounter = 0;
+
+                function checkSuccess() {
+                    successCounter++;
+                    if (successCounter == 2) {
+                         resolve();
+                    }
+                }
+                 
+                function postTokenRefreshChecks(sender, error) {
+                    try {
+                        TestCase.assertEqual(error, accessTokenRefreshed);
+                        TestCase.assertEqual(sender.url, `realm://localhost:9080/${user.identity}/myrealm`);
+                        checkSuccess();
+                    }
+                    catch (e) {
+                        reject(e)
+                    }
+                };
+
+                // Let the error handler trigger our checks when the access token was refreshed.
+                postTokenRefreshChecks._notifyOnAccessTokenRefreshed = accessTokenRefreshed;
+
+                const config = { sync: { user, url: 'realm://localhost:9080/~/myrealm', error: postTokenRefreshChecks } };
+                Realm.openAsync(config, (error, realm) => {
+                    if (error) {
+                        reject(error);
+                        return;
+                    }
+
+                    const session = realm.syncSession;
+                    TestCase.assertInstanceOf(session, Realm.Sync.Session);
+                    TestCase.assertEqual(session.user.identity, user.identity);
+                    TestCase.assertEqual(session.config.url, config.sync.url);
+                    TestCase.assertEqual(session.config.user.identity, config.sync.user.identity);
+                    TestCase.assertEqual(session.state, 'active');
+                    
+                    checkSuccess();
+                });
             });
         });
     },
diff --git a/tests/spec/unit_tests.js b/tests/spec/unit_tests.js
index d84d349c..2826381b 100644
--- a/tests/spec/unit_tests.js
+++ b/tests/spec/unit_tests.js
@@ -28,6 +28,10 @@ const Realm = require('realm');
 const RealmTests = require('../js');
 
 jasmine.DEFAULT_TIMEOUT_INTERVAL = 30000;
+const isDebuggerAttached = typeof v8debug === 'object';
+if (isDebuggerAttached) {
+    jasmine.DEFAULT_TIMEOUT_INTERVAL = 3000000;
+}
 
 // Create this method with appropriate implementation for Node testing.
 Realm.copyBundledRealmFiles = function() {