We study the expected value of support functions of random polytopes in a certain direction, where the random polytope is given by independent random vectors uniformly distributed in an isotropic convex body. All results are obtained by an utterly novel approach, using probabilistic estimates in connection with Orlicz norms that were not used in this connection before.√ n for some 1991 Mathematics Subject Classification. Primary 52A22, Secondary 52A23, 05D40, 46B09.