Well, the answer is yes, and no.<br /><br />"Yes," because the link between supernovae/hypernovae and the majority of GRBs seems to be quite strong, as determined by study of GRB afterglows. <br /><br />"No," because so far theory suggests that only stars too massive to become neutron stars can generate a GRB when they explode, so there are probably a number of supernovae/hypernovae that don't cause GRBs. Also, there are some GRBs that can't easily be explained by SN models, and many astronomers have settled on merging neutron stars as the culprits for these out-liers.