diff --git a/packages/core/src/application_init.ts b/packages/core/src/application_init.ts
index b801ab26b4..554c120d9d 100644
--- a/packages/core/src/application_init.ts
+++ b/packages/core/src/application_init.ts
@@ -27,11 +27,11 @@ export class ApplicationInitStatus {
   private resolve: Function;
   private reject: Function;
   private initialized = false;
-  private _donePromise: Promise<any>;
-  private _done = false;
+  public readonly donePromise: Promise<any>;
+  public readonly done = false;
 
   constructor(@Inject(APP_INITIALIZER) @Optional() private appInits: (() => any)[]) {
-    this._donePromise = new Promise((res, rej) => {
+    this.donePromise = new Promise((res, rej) => {
       this.resolve = res;
       this.reject = rej;
     });
@@ -46,7 +46,7 @@ export class ApplicationInitStatus {
     const asyncInitPromises: Promise<any>[] = [];
 
     const complete = () => {
-      this._done = true;
+      (this as{done: boolean}).done = true;
       this.resolve();
     };
 
@@ -66,8 +66,4 @@ export class ApplicationInitStatus {
     }
     this.initialized = true;
   }
-
-  get done(): boolean { return this._done; }
-
-  get donePromise(): Promise<any> { return this._donePromise; }
 }
diff --git a/packages/core/src/application_ref.ts b/packages/core/src/application_ref.ts
index 8f131e8857..b024bfb626 100644
--- a/packages/core/src/application_ref.ts
+++ b/packages/core/src/application_ref.ts
@@ -335,14 +335,27 @@ export class ApplicationRef {
   /** @internal */
   static _tickScope: WtfScopeFn = wtfCreateScope('ApplicationRef#tick()');
   private _bootstrapListeners: ((compRef: ComponentRef<any>) => void)[] = [];
-  private _rootComponents: ComponentRef<any>[] = [];
-  private _rootComponentTypes: Type<any>[] = [];
   private _views: InternalViewRef[] = [];
   private _runningTick: boolean = false;
   private _enforceNoNewChanges: boolean = false;
-  private _isStable: Observable<boolean>;
   private _stable = true;
 
+  /**
+   * Get a list of component types registered to this application.
+   * This list is populated even before the component is created.
+   */
+  public readonly componentTypes: Type<any>[] = [];
+
+  /**
+   * Get a list of components registered to this application.
+   */
+  public readonly components: ComponentRef<any>[] = [];
+
+  /**
+   * Returns an Observable that indicates when the application is stable or unstable.
+   */
+  public readonly isStable: Observable<boolean>;
+
   /** @internal */
   constructor(
       private _zone: NgZone, private _console: Console, private _injector: Injector,
@@ -397,7 +410,8 @@ export class ApplicationRef {
       };
     });
 
-    this._isStable = merge(isCurrentlyStable, share.call(isStable));
+    (this as{isStable: Observable<boolean>}).isStable =
+        merge(isCurrentlyStable, share.call(isStable));
   }
 
   /**
@@ -428,7 +442,7 @@ export class ApplicationRef {
       componentFactory =
           this._componentFactoryResolver.resolveComponentFactory(componentOrFactory) !;
     }
-    this._rootComponentTypes.push(componentFactory.componentType);
+    this.componentTypes.push(componentFactory.componentType);
 
     // Create a factory associated with the current module if it's not bound to some other
     const ngModule = componentFactory instanceof ComponentFactoryBoundToModule ?
@@ -483,17 +497,6 @@ export class ApplicationRef {
     }
   }
 
-  /**
-   * Get a list of component types registered to this application.
-   * This list is populated even before the component is created.
-   */
-  get componentTypes(): Type<any>[] { return this._rootComponentTypes; }
-
-  /**
-   * Get a list of components registered to this application.
-   */
-  get components(): ComponentRef<any>[] { return this._rootComponents; }
-
   /**
    * Attaches a view so that it will be dirty checked.
    * The view will be automatically detached when it is destroyed.
@@ -517,7 +520,7 @@ export class ApplicationRef {
   private _loadComponent(componentRef: ComponentRef<any>): void {
     this.attachView(componentRef.hostView);
     this.tick();
-    this._rootComponents.push(componentRef);
+    this.components.push(componentRef);
     // Get the listeners lazily to prevent DI cycles.
     const listeners =
         this._injector.get(APP_BOOTSTRAP_LISTENER, []).concat(this._bootstrapListeners);
@@ -526,7 +529,7 @@ export class ApplicationRef {
 
   private _unloadComponent(componentRef: ComponentRef<any>): void {
     this.detachView(componentRef.hostView);
-    remove(this._rootComponents, componentRef);
+    remove(this.components, componentRef);
   }
 
   /** @internal */
@@ -539,11 +542,6 @@ export class ApplicationRef {
    * Returns the number of attached views.
    */
   get viewCount() { return this._views.length; }
-
-  /**
-   * Returns an Observable that indicates when the application is stable or unstable.
-   */
-  get isStable(): Observable<boolean> { return this._isStable; }
 }
 
 function remove<T>(list: T[], el: T): void {
diff --git a/packages/core/src/change_detection/differs/default_iterable_differ.ts b/packages/core/src/change_detection/differs/default_iterable_differ.ts
index b74c7a7a13..dc2c08ec18 100644
--- a/packages/core/src/change_detection/differs/default_iterable_differ.ts
+++ b/packages/core/src/change_detection/differs/default_iterable_differ.ts
@@ -26,8 +26,8 @@ const trackByIdentity = (index: number, item: any) => item;
  * @deprecated v4.0.0 - Should not be part of public API.
  */
 export class DefaultIterableDiffer<V> implements IterableDiffer<V>, IterableChanges<V> {
-  private _length: number = 0;
-  private _collection: NgIterable<V>|null = null;
+  public readonly length: number = 0;
+  public readonly collection: V[]|Iterable<V>|null;
   // Keeps track of the used records at any point in time (during & across `_check()` calls)
   private _linkedRecords: _DuplicateMap<V>|null = null;
   // Keeps track of the removed records at any point in time during `_check()` calls.
@@ -48,10 +48,6 @@ export class DefaultIterableDiffer<V> implements IterableDiffer<V>, IterableChan
 
   constructor(trackByFn?: TrackByFunction<V>) { this._trackByFn = trackByFn || trackByIdentity; }
 
-  get collection() { return this._collection; }
-
-  get length(): number { return this._length; }
-
   forEachItem(fn: (record: IterableChangeRecord_<V>) => void) {
     let record: IterableChangeRecord_<V>|null;
     for (record = this._itHead; record !== null; record = record._next) {
@@ -171,9 +167,9 @@ export class DefaultIterableDiffer<V> implements IterableDiffer<V>, IterableChan
     let item: V;
     let itemTrackBy: any;
     if (Array.isArray(collection)) {
-      this._length = collection.length;
+      (this as{length: number}).length = collection.length;
 
-      for (let index = 0; index < this._length; index++) {
+      for (let index = 0; index < this.length; index++) {
         item = collection[index];
         itemTrackBy = this._trackByFn(index, item);
         if (record === null || !looseIdentical(record.trackById, itemTrackBy)) {
@@ -206,11 +202,11 @@ export class DefaultIterableDiffer<V> implements IterableDiffer<V>, IterableChan
         record = record._next;
         index++;
       });
-      this._length = index;
+      (this as{length: number}).length = index;
     }
 
     this._truncate(record);
-    this._collection = collection;
+    (this as{collection: V[] | Iterable<V>}).collection = collection;
     return this.isDirty;
   }
 
diff --git a/packages/core/src/di/injection_token.ts b/packages/core/src/di/injection_token.ts
index 5d9b8327b3..9fd360fa62 100644
--- a/packages/core/src/di/injection_token.ts
+++ b/packages/core/src/di/injection_token.ts
@@ -29,10 +29,10 @@
  * @stable
  */
 export class InjectionToken<T> {
+  /** @internal */
+  readonly ngMetadataName = 'InjectionToken';
+
   constructor(protected _desc: string) {}
 
   toString(): string { return `InjectionToken ${this._desc}`; }
-
-  /** @internal */
-  get ngMetadataName() { return 'InjectionToken'; }
 }
diff --git a/packages/core/src/di/reflective_injector.ts b/packages/core/src/di/reflective_injector.ts
index 6b7f4c47d0..1d4999fd1c 100644
--- a/packages/core/src/di/reflective_injector.ts
+++ b/packages/core/src/di/reflective_injector.ts
@@ -282,8 +282,7 @@ export class ReflectiveInjector_ implements ReflectiveInjector {
   _constructionCounter: number = 0;
   /** @internal */
   public _providers: ResolvedReflectiveProvider[];
-  /** @internal */
-  public _parent: Injector|null;
+  public readonly parent: Injector|null;
 
   keyIds: number[];
   objs: any[];
@@ -292,7 +291,7 @@ export class ReflectiveInjector_ implements ReflectiveInjector {
    */
   constructor(_providers: ResolvedReflectiveProvider[], _parent?: Injector) {
     this._providers = _providers;
-    this._parent = _parent || null;
+    this.parent = _parent || null;
 
     const len = _providers.length;
 
@@ -309,8 +308,6 @@ export class ReflectiveInjector_ implements ReflectiveInjector {
     return this._getByKey(ReflectiveKey.get(token), null, notFoundValue);
   }
 
-  get parent(): Injector|null { return this._parent; }
-
   resolveAndCreateChild(providers: Provider[]): ReflectiveInjector {
     const ResolvedReflectiveProviders = ReflectiveInjector.resolve(providers);
     return this.createChildFromResolved(ResolvedReflectiveProviders);
@@ -318,7 +315,7 @@ export class ReflectiveInjector_ implements ReflectiveInjector {
 
   createChildFromResolved(providers: ResolvedReflectiveProvider[]): ReflectiveInjector {
     const inj = new ReflectiveInjector_(providers);
-    inj._parent = this;
+    (inj as{parent: Injector | null}).parent = this;
     return inj;
   }
 
@@ -436,7 +433,7 @@ export class ReflectiveInjector_ implements ReflectiveInjector {
     let inj: Injector|null;
 
     if (visibility instanceof SkipSelf) {
-      inj = this._parent;
+      inj = this.parent;
     } else {
       inj = this;
     }
@@ -445,7 +442,7 @@ export class ReflectiveInjector_ implements ReflectiveInjector {
       const inj_ = <ReflectiveInjector_>inj;
       const obj = inj_._getObjByKeyId(key.id);
       if (obj !== UNDEFINED) return obj;
-      inj = inj_._parent;
+      inj = inj_.parent;
     }
     if (inj !== null) {
       return inj.get(key.token, notFoundValue);
diff --git a/packages/core/src/di/reflective_key.ts b/packages/core/src/di/reflective_key.ts
index 765f3fded6..bc51fcb649 100644
--- a/packages/core/src/di/reflective_key.ts
+++ b/packages/core/src/di/reflective_key.ts
@@ -27,6 +27,7 @@ import {resolveForwardRef} from './forward_ref';
  * @deprecated No replacement
  */
 export class ReflectiveKey {
+  public readonly displayName: string;
   /**
    * Private
    */
@@ -34,13 +35,9 @@ export class ReflectiveKey {
     if (!token) {
       throw new Error('Token must be defined!');
     }
+    this.displayName = stringify(this.token);
   }
 
-  /**
-   * Returns a stringified token.
-   */
-  get displayName(): string { return stringify(this.token); }
-
   /**
    * Retrieves a `Key` for a token.
    */
diff --git a/packages/core/src/linker/query_list.ts b/packages/core/src/linker/query_list.ts
index 8dae2c824f..34fc10d5b2 100644
--- a/packages/core/src/linker/query_list.ts
+++ b/packages/core/src/linker/query_list.ts
@@ -37,11 +37,10 @@ import {getSymbolIterator} from '../util';
  * @stable
  */
 export class QueryList<T>/* implements Iterable<T> */ {
-  private _dirty = true;
+  public readonly dirty = true;
   private _results: Array<T> = [];
-  private _emitter = new EventEmitter();
+  public readonly changes: Observable<any> = new EventEmitter();
 
-  get changes(): Observable<any> { return this._emitter; }
   get length(): number { return this._results.length; }
   get first(): T { return this._results[0]; }
   get last(): T { return this._results[this.length - 1]; }
@@ -98,21 +97,18 @@ export class QueryList<T>/* implements Iterable<T> */ {
 
   reset(res: Array<T|any[]>): void {
     this._results = flatten(res);
-    this._dirty = false;
+    (this as{dirty: boolean}).dirty = false;
   }
 
-  notifyOnChanges(): void { this._emitter.emit(this); }
+  notifyOnChanges(): void { (this.changes as EventEmitter<any>).emit(this); }
 
   /** internal */
-  setDirty() { this._dirty = true; }
-
-  /** internal */
-  get dirty() { return this._dirty; }
+  setDirty() { (this as{dirty: boolean}).dirty = true; }
 
   /** internal */
   destroy(): void {
-    this._emitter.complete();
-    this._emitter.unsubscribe();
+    (this.changes as EventEmitter<any>).complete();
+    (this.changes as EventEmitter<any>).unsubscribe();
   }
 }
 
diff --git a/packages/core/src/version.ts b/packages/core/src/version.ts
index 3a662a849c..0d5b462866 100644
--- a/packages/core/src/version.ts
+++ b/packages/core/src/version.ts
@@ -12,13 +12,15 @@
  * @stable
  */
 export class Version {
-  constructor(public full: string) {}
+  public readonly major: string;
+  public readonly minor: string;
+  public readonly patch: string;
 
-  get major(): string { return this.full.split('.')[0]; }
-
-  get minor(): string { return this.full.split('.')[1]; }
-
-  get patch(): string { return this.full.split('.').slice(2).join('.'); }
+  constructor(public full: string) {
+    this.major = full.split('.')[0];
+    this.minor = full.split('.')[1];
+    this.patch = full.split('.').slice(2).join('.');
+  }
 }
 
 /**
diff --git a/packages/core/src/view/refs.ts b/packages/core/src/view/refs.ts
index bb9040f601..df2f6bfa8b 100644
--- a/packages/core/src/view/refs.ts
+++ b/packages/core/src/view/refs.ts
@@ -101,18 +101,21 @@ class ComponentFactory_ extends ComponentFactory<any> {
 }
 
 class ComponentRef_ extends ComponentRef<any> {
+  public readonly hostView: ViewRef;
+  public readonly instance: any;
+  public readonly changeDetectorRef: ChangeDetectorRef;
   private _elDef: NodeDef;
   constructor(private _view: ViewData, private _viewRef: ViewRef, private _component: any) {
     super();
     this._elDef = this._view.def.nodes[0];
+    this.hostView = _viewRef;
+    this.changeDetectorRef = _viewRef;
+    this.instance = _component;
   }
   get location(): ElementRef {
     return new ElementRef(asElementData(this._view, this._elDef.index).renderElement);
   }
   get injector(): Injector { return new Injector_(this._view, this._elDef); }
-  get instance(): any { return this._component; };
-  get hostView(): ViewRef { return this._viewRef; };
-  get changeDetectorRef(): ChangeDetectorRef { return this._viewRef; };
   get componentType(): Type<any> { return <any>this._component.constructor; }
 
   destroy(): void { this._viewRef.destroy(); }