We discuss the development of the theory of electroweak radiative corrections
and its role in testing the Standard Model, predicting the top quark mass,
constraining the Higgs boson mass, and searching for deviations that may signal
the presence of new physics.Comment: 19 pages, acknowledgments added, J.J.Sakurai Prize Talk, APS Meeting,
Albuquerque, N.M., April 2002. To appear in a future issue of Journal of
Physics