  We propose a new set of supersymmetric benchmark scenarios, taking into
account the constraints from LEP, b to s gamma, g_mu - 2 and cosmology. We work
in the context of the constrained MSSM (CMSSM) with universal soft
supersymetry-breaking masses and assume that R parity is conserved. We propose
benchmark points that exemplify the different generic possibilities, including
focus-point models, points where coannihilation effects on the relic density
are important, and points with rapid relic annihilation via direct-channel
Higgs poles. We discuss the principal decays and signatures of the different
classes of benchmark scenarios, and make initial estimates of the physics
reaches of different accelerators, including the Tevatron collider, the LHC,
and e+ e- colliders in the sub- and multi-TeV ranges. We stress the
complementarity of hadron and lepton colliders, with the latter favoured for
non-strongly-interacting particles and precision measurements. We mention
features that could usefully be included in future versions of supersymmetric
event generators.
