Electroweak interference in e+e- annihilation

High precision results from PEP and the extended energy range of PETRA now allow accurate comparison of experimental results with theory. One-loop weak corrections have been calculated in both Weinberg-Salam and Glashow schemes and are needed in these comparisons. The Z0 propagator effect is seen and the asymmetries agree, with a 7% error, with rho = 1. The μ-pair asymmetry is a little high. The effects of normalisation errors are discussed. The success of the GWS theory in the leptonic sector places limits on new phenomena. The weak isospins of c- and b-quarks have been measured and are consistent with weak isodoublets, so that a t-quark is required by the asymmetry measurements. 59 refs.