  We consider models of dynamical supersymmetry breaking in which the
extremization of a tree-level superpotential conflicts with a quantum
constraint. We show that in such models the low-energy effective theory near
the origin of moduli space is an O'Raifeartaigh model, and the sign of the
mass-squared for the pseudo-flat direction at the origin is calculable. We
analyze vector-like models with gauge groups SU(N) and Sp(2N) with and without
global symmetries. In all cases there is a stable minimum at the origin with an
unbroken U(1)_R symmetry.
