The progenitors of at least some long gamma-ray bursts have been firmly identified as massive star collapses, through the association with Ibc supernovae. The observational and derived physical properties of these supernovae show a tight clustering, pointing to similar progenitors. Similarly, there are increasing theoretical indications that the properties of the binary neutron star progenitors of short gamma-ray bursts should reside in a rather narrow region of the parameter space. Why, then, are gamma-ray bursts so diverse? In this talk I will discuss the feasibility of a unification of gamma-ray bursts as being produced by jets with a quasi- universal angular structure, with the viewing angle (and other extrinsic parameters) driving most of the diversity we observe. Such unification would have extremely interesting consequences both on our understanding of their progenitors and on the use of these events as standard candles or, in conjunction with gravitational wave observations, as standard sirens.