Assertions in VB.NET?

Blake Watson talks about RemObject’s Chrome, a Pascal that’s not Delphi, on DevSource. There he talks about “class contracts“, a concept I’ve liked since I first read Bertrand Meyer‘s Object-Oriented Software Contruction, 1st edition back in the late 80’s back, and a feature I’d love to see in VB.NET. Whaddayasay Mr. Vick?