John,
You got me on the right track.

DataTable dtTransDate = dSRA.Tables["RATRANS"].DefaultView.ToTable(true, "transdate");

It returns a distinct result like I wanted but it only seems to work on my main form. For now I have this in the rightmouse event of a button on my main form.

My intent was to have another form or dialog pop up and provide the combobox with the distinct dates. If I move the statement to the second (called) form my dataset (dSRA) is not known.

Do I need to pass the databale or dataset as a reference to the new form in some way?

Sorry for all the questions but I'm very new at the whole C# thing. And if this is way beyond a simple answer just say so.

Thanks