Electroweak Physics at HERA:

: A high luminosity upgrade of HERA will allow the measurement of standard model parameters and the neutral current couplings of quarks. These results will have to be consistent with other precision measurements or indicate traces of new physics. The analysis of W production will complement future results of LEP 2 and the Tevatron. We summarize the main results and conclusions obtained by the working group on Electroweak Physics concerning the potential of future experimentation at HERA. 1 Introduction The DESY ep collider HERA is a unique place to explore the structure of the proton, in particular at low Bjorken x and large momentum transfer Q 2 and at the same time to probe the theory of electroweak interactions in the regime of large spacelike Q 2 , extending previous measurements at fixed target experiments by more than two orders of magnitude. This is complementary to what can be accessed at LEP and hadron colliders in searches for deviations from the standard model (SM). In ..