  A variety of arguments suggest that the most common form of gamma-ray bursts
(GRBs), those longer than a few seconds, involve the formation of black holes
in supernova-like events. Two kinds of ``collapsar'' models are discussed,
those in which the black hole forms promptly - a second or so after iron core
collapse - and those in which formation occurs later, following ``fallback''
over a period of minutes to hours. In most cases, extraction of energy from a
rapidly accreting disk (and a rapidly rotating black hole) is achieved by
magnetohydrodynamical processes, although neutrino-powered models remain viable
in cases where the accretion rate is >0.05 solar masses per second. GRBs are
but one observable phenomenon accompanying black hole birth and other
possibilities are discussed, some of which (long, faint GRBs and soft x-ray
transients) may await discovery. Since they all involve black holes of similar
mass accreting one to several M\sun, collapsars have a nearly standard total
energy, around 10**52 erg, but both the fraction of that energy ejected as
highly relativistic matter and the distribution of that energy with angle can
be highly variable. An explanation is presented why inferred GRB luminosity
might correlate inversely with time scales and arguments are given against the
production of ordinary GRBs by supergiant stars.
