ASP.NET 2.0 GridView: how-to allow edit+delete only some users / groups

[Rainer Kroos]

Hi,
I will use ASP.NET 2.0 GridView controls for SQL Server data viewing /
editing.
Until now I could not find any information how to do this:

GridView controls shall be used to show read-only data to some users /
groups. They shall not see the Edit / Delete / Select controls in a data
row. Other users / groups should see these controls in the same GridView and
are allowed to use them.

How can this be done?
Thanks for any answer.

Rainer Kroos