  This is a report of the Electroweak Symmetry Breaking and Beyond the Standard
Model Working Group which was prepared for the Division of Particles and Fields
Committee for Long Term Planning. We study the phenomenology of electroweak
symmetry breaking and attempt to quantify the "physics reach" of present and
future colliders. Our investigations encompass the Standard Model (with one
doublet of Higgs scalars) and approaches to physics beyond the Standard Model.
These include models of low energy supersymmetry, technicolor and other
approaches to dynamical electroweak symmetry breaking, and a variety of
extensions of the Standard Model with new particles and interactions ({\it
e.g.}, non-minimal Higgs sectors, new gauge bosons and/or exotic fermions, {\it
etc.}). Signals of new physics in precision measurements arising from virtual
processes (which can result, for example, in ``anomalous'' couplings of
Standard Model particles) are also considered. Finally, we examine experimental
issues associated with the study of electroweak symmetry breaking and the
search for new physics at present and future hadron and $e^+e^-$ colliders.
