Hello Jesse,

I have been looking into your question and I can suggest you define a style for the ‘GroupByRecordPresenter’ and manipulate the value of the tooltip via value converter like e.g. :

      <local2:MyConverter x:Key="con"/>

      <Style TargetType="{x:Type igDP:GroupByRecordPresenter}">

            <Setter Property="ToolTip" Value="{Binding Converter={StaticResource con}}"></Setter>

        </Style>

…

public class MyConverter : IValueConverter

    {

        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)

        {

            return (((value as GroupByRecord).ChildRecords[0] as DataRecord).DataItem as Product).CategoryID;

        }

        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)

        {

            return value;

        }

    }

This way you will have a tooltip showing data from the DataItem.

Let me know , if you need any further assistance on this matter.