  We discuss the quantization of theories which are formulated using
compensating fields. In particular, we discuss the relation between the
components formulation and the superspace formulation of supergravity theories.
The requirement that the compensating field can be eliminated at the quantum
level gives rise to on-shell constraints on the operators of the theory. In
some cases, the constraints turn out to be physically unacceptable. Using these
considerations we show that new minimal supergravity is in general anomalous.
