We discuss aspects of grand unified theories (GUTs) combined with N=1 local supersymmetry, interpreting the general form of simple supergravity theory as a phenomenological effective lagrangian applicable at energies less than the Planck mass. We consider light fermion masses, baryon decay and a possible resolution of the QCD vacuum angle θ problem in this general framework. We propose two mechanisms for weak symmetry breaking based on radiative corrections originating from supergravity effects, notably by a direct gaugino mass in theories with non-minimal coupling to N=1 supergravity. We give a specific example of a GUT employing this mechanism.