  The initial burst of a gamma ray burst (GRB) is usually followed by a
longer-lived afterglow emitted at longer wavelengths. The evidence for a
physical connection between GRBs and core collapse supernovae (SN) has
increased since the discovery of GRB afterglows. So far SN signatures have been
found in only a few GRBs. Here we propose the possibility of a GRB triggering
the collapse of a WR or RG star in a binary system producing a SN, and typical
signatures. We also look at the effects of GRBs on MS and WD stars in the
neighbourhood. The possibility of GRBs retarding star formation in an
interstellar cloud is also discussed.
