C# WPF Bind a single GridViewColumn to a list of items

Hi,

I have a list of custom objects.  One of the properties (called 'Names' for instance) in that object is a List<string> containing peoples names.

I want to bind my list of custom objects to the gridview, but would like the 'Names' column for each row to display all the names in the Names property (preferably formatted as comma separated).

I.E

DATE               TOPIC                NAMES
12/01/13          Cheese          Bill, Mickey, Karen,John
14/03/13          Armadillos     Arthur, Albert, Susan, Helen, Mark

I'm using MVVM, so any solution should take that into account.

Thanks

Mick