If I do this inside a User Control:
NavigationService.Navigate(new Uri(\"/Alliance.xaml\", UriKind.Relative));
it says this error:
Here is another solution for Silverlight for Windows Phone 8:
public Page Page { get; set; }
this.Loaded += delegate { Page = (Application.Current.RootVisual as Frame).Content as Page; };
Page.NavigationService.Navigate(new Uri("/Alliance.xaml", UriKind.Relative));