Yes I have added the reference correctly

For somereason when i run the application I get error Provide value on 'System.Windows.Data.Binding' and this is on same line where i give the Converter

What does the ElementName signify

Also I dont get intellisence for FirstOrDefault

Hello,

I have checked the sample you provided. I was not able to debug it and to make sure everything works. However I got the general idea. Here are few pointers:

You need to provide the DetailsTable1(or DetailsView1 - don't know are they different) - basically you need to provide  ConverterParameter the table that is mapping Id to TextDescription. Your TextBlock code should look something like this:

<TextBlock Text="{Binding Path=detailid1,
    Converter={StaticResource LookupValueConverter},
    ConverterParameter={Binding ElementName=LayoutRoot, Path=DataContext.DetailsView1}}" />

After that in the Converter you look up the parameter(you should know and cast to the type it is). The Convert method should look :

public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)  
{
    var viewY = parameter as EntitySet<DetailsView1>;

    return viewY.FirstOrDefault(row => row.Id == (int)value).Description;
}

HTH,