Angular2 Can't bind to DIRECTIVE since it isn't a known property of element

When wrapping a property in brackets [] you're trying to bind to it. So you have to declare it as an @Input.

import { Directive, Input } from '@angular/core';

@Directive({
 selector: '[appContenteditableModel]'
})
export class ContenteditableModelDirective {

  @Input()
  appContenteditableModel: string;

  constructor() { }

}

The important part is, that the member (appContenteditableModel) needs to be named as the property on the DOM node (and, in this case, the directive selector).

If you're using a shared module to define the directive make sure it is both declared and exported by module it's defined in.

// this is the SHARED module, where you're defining directives to use elsewhere
@NgModule({
  imports: [
    CommonModule
  ],
  declarations: [NgIfEmptyDirective, SmartImageDirective],
  exports: [NgIfEmptyDirective, SmartImageDirective]
})

For me the fix was moving the directive references from root app.module.ts (the lines for import, declarations, and/or exports) to the more specific module src/subapp/subapp.module.ts my component belonged to.