  This talk gives an overview of the recent development in the study of
non-perturbative fermion-boson vertex in quenched QED towards achieving that
the fermion propagator satisfies the Ward-Takahashi identity, is
multiplicatively renormalizable, agrees with perturbation theory for weak
couplings and has a critical coupling for dynamical mass generation that is
strictly gauge independent. The use of such a vertex may lead to a realistic
calculation of t(tbar) condensates as the source of electroweak symmetry
breaking. (Talk given at The Advanced Study Institute on Frontiers in Particle
Physics, Cargese, Ajaccio, France, August 1-13, 1994.)
