  In rigid supersymmetry, generic models of dynamical supersymmetry breaking
contain a light Goldstone boson, called the R axion. We show that supergravity
effects explicitly break the R symmetry and give mass to the R axion. For
visible and renormalizable hidden sector models, the massive R axion is free
from astrophysical and cosmological problems. For nonrenormalizable hidden
sector models, the R axion suffers from cosmological difficulties similar to
those of the moduli fields in string theory.
