Bounds on {gamma} from CP violation measurements in B{yields}{pi}{sup +}{pi}{sup -} and B{yields}{psi}K{sub S}

We study the determination of {gamma} from CP-violating observables in B{yields}{pi}{sup +}{pi}{sup -} and B{yields}{psi}K{sub S}. This determination requires theoretical input to one combination of hadronic parameters. We show that a mild assumption about this quantity may allow bounds to be placed on {gamma}, but we stress the pernicious effects that an eightfold discrete ambiguity has on such an analysis. The bounds are discussed as a function of the direct (C) and interference (S) CP-violating observables obtained from time-dependent B{yields}{pi}{sup +}{pi}{sup -} decays, and their behavior in the presence of new physics effects in B-B-bar mixing is studied.