This book presents several precision measurements performed on atomic cesium and related to ongoing efforts toward a new measurement of the Weinberg mixing angle QW at low momentum transfer. The ultimate goal of this research program is an improved measurement of the extremely weak electric-dipole transition moment Epv of the 6s 2S1/2 7s 2S1/2 transition of cesium, which is strictly electric-dipole forbidden without the weak force. Due to state mixing by the weak interaction, however, the optical transition is allowed, albeit very weakly, 10 11ea0. The magnitude of Epv yields the weak mixing angle QW and improving the precision of QW provides a direct test of the standard model of particle physics. The three specific measurements described in this thesis are: hyperfine coupling constants of several states; the static Stark polarizability of the 7s
