Sarid Research in theoretical particle physics will explore new and promising directions in the phenomenology of supersymmetric models. Laboratory signatures of wide classes of gauge-mediated supersymmetric theories will be identified, constraints on unified theories will be derived and related directly to experimentally-observable quantities, the implications for fundamental explanations of elementary particle masses will be explored, and stronger ties will be forged with astrophysics and cosmology. Supersymmetry is the leading candidate for the physics underlying the spectacularly successful current "standard model" of particle physics, and a dedicated investigation of its observable implications is crucial to its discovery and study. ***