  The use of spin observables to study the semi-leptonic and non-leptonic weak
interaction in atoms and nuclei is surveyed. In particular, the use of
semi-leptonic neutral current scattering and atomic parity violation to search
for physics beyond the Standard Model is reviewed. The status of nuclear parity
violation as a probe of the weak N-N interaction is surveyed. Possible atomic
and nuclear signatures of parity conserving, time-reversal violating
interactions are also discussed.
