  We show that the holomorphic Wilsonian beta-function of a renormalizable
asymptotically free supersymmetric gauge theory with an arbitrary semi-simple
gauge group, matter content, and renormalizable superpotential is exhausted at
1-loop with no higher loops and no non-perturbative contributions. This is a
non-perturbative extension of the well known result of Shifman and Vainshtein.
