  The parity violation programs at MIT-Bates, Jefferson Lab and Mainz are
presently focused on developing a better understanding of the sea-quark
contributions to the vector matrix elements of nucleon structure. The success
of these programs will allow precise semi-leptonic tests of the Standard Model
such as that planned by the QWeak collaboration. In order to determine the
vector matrix elements, a good understanding of the nucleon's axial vector form
factor as seen by an electron, G^e_A, is also required. While the vector
electroweak form factors provide information about the nucleon's charge and
magnetism, the axial form factor is related to the nucleon's spin. Its Q2=0
value at leading order, g_A, is well known from nucleon and nuclear beta decay,
and its precise determination is of interest for tests of CKM unitarity. Most
information about its Q2 dependence comes from quasielastic neutrino scattering
and from pion electroproduction, and a recent reanalysis of the neutrino data
have brought these two types of measurements into excellent agreement. However,
these experiments are not sensitive to additional higher order corrections,
such as nucleon anapole contributions, that are present in parity-violating
electron scattering. In this talk I will attempt to review what is presently
known about the axial form factor and its various pieces including the higher
order contributions, discuss the the various experimental sectors, and give an
update on its determination through PV electron scattering.

Nuclear Experiment