  Gamma-ray bursts are known to be sources of high-energy gamma rays, and are
likely to be sources of high-energy cosmic rays and neutrinos. Following a
short review of observations of GRBs at multi-MeV energies and above, the
physics of leptonic and hadronic models of GRBs is summarized. Evidence for two
components in BATSE and EGRET/TASC data suggest that GRBs are sources of
high-energy cosmic rays. GLAST observations will reveal the high-energy
gamma-ray power and energy releases from GRBs, and will provide detailed
knowledge of anomalous high-energy emission components, but confirmation of
cosmic ray acceleration must await 100 TeV -- PeV neutrino detection from GRBs.
