Heavy Baryon Chiral Perturbation Theory and Reparametrization Invariance

We examine the constraints imposed by reparametrization invariance on heavy-baryon chiral perturbation theory (HBChPT). We study the case of three flavors and consider both the strong and weak $(|\ensuremath{\Delta}S|=1)$ interaction sectors. Some of the parameters in the HBChPT Lagrangian are fixed as a consequence of re- parametrization invariance. We discuss the consequences for the calculation of hyperon weak radiative decays in HBChPT.