2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/37481The H1 and ZEUS collaborations have searched for signals of physics beyond the Standard Model in ep collisions at a center-of-mass energy of 301-319 GeV. During the HERA I phase each experiment accumulated an integrated luminosity of about 110 pb^{-1} for e^+p and about 15 pb^{-1} for e^-p collisions. The data have been analysed searching for contact interaction effects, leptoquarks, lepton flavor violation, squarks in R-parity violating supersymmetric models, excited fermions and FCNC single top production. In this article a summary of the results is given.To appear in the proceedings of 38th Rencontres de Moriond (Electroweak Interactions and Unified Theories), Les Arcs, March 15-22, 2003High Energy Physics - Experimenttext