This grant supports research by three New York University (NYU) faculty, a postdoctoral research associate and three graduate students. The project is the study of collisions of antiprotons with protons at 2 TeV in the Tevatron collider at Fermilab. The group are members of the D0 collaboration who have built and put into operation a large, complex apparatus that detects the interaction products and determines their properties. Since its existence is a crucial component of the Standard Model paradigm, the D0 experiment has a major goal the discovery of the top quark and determination of some of its properties. D0 is one of the two experiments that will continue to have that capability in the next few years. Many different kinds of stringent tests of QCD and electroweak theoretical predictions also will result. The NYU group's major current interest is the electroweak sector. They are prepared to make a precise measurement of the W-boson mass with which to confront the theory.