  The relation between the trace and R-current anomalies in supersymmetric
theories implies that the U$(1)_RF^2$, U$(1)_R$ and U$(1)_R^3$ anomalies which
are matched in studies of N=1 Seiberg duality satisfy positivity constraints.
Some constraints are rigorous and others conjectured as four-dimensional
generalizations of the Zamolodchikov $c$-theorem. These constraints are tested
in a large number of N=1 supersymmetric gauge theories in the non-Abelian
Coulomb phase, and they are satisfied in all renormalizable models with unique
anomaly-free R-current, including those with accidental symmetry. Most striking
is the fact that the flow of the Euler anomaly coefficient, $a_{UV}-a_{IR}$, is
always positive, as conjectured by Cardy.
