  The proposal to perform polarized proton-proton collisions at collider
energies at RHIC is reviewed. After a brief reminder of the desirability of
high energy spin physics measurements, we discuss the machine parameters and
detector features which are taken to define a program of spin physics at RHIC.
Some of the many physics processes which can provide information on polarized
parton distributions and the spin-dependence of QCD and the electroweak model
at RHIC energies are discussed. (To appear in the proceedings of the
International Symposium on Particle Theory and Phenomenology, Iowa State
University, May 22-24, 1995.)
