  We present Fabry-Perot and multi-object spectroscopy of the galaxies in
Hickson compact group 31 (HCG31). Based upon our H$\alpha$ data cubes, galaxies
A and C are a single entity, showing no discontinuity in their kinematics.
Kinematically, galaxy E is probably a component of the A+C complex; otherwise
it is a recently detached fragment. Galaxy F appears, both kinematically and
chemically, to have formed from material tidally removed from the A+C complex.
Galaxies B and G are kinematically distinct from this complex. Galaxy Q also
has a radial velocity compatible with group membership. Galaxies A, B, C, and F
have nearly identical oxygen abundances, despite spanning a luminosity range of
5$ $mag. Galaxy B's oxygen abundance is normal for its luminosity, while galaxy
F's abundance is that expected given its origin as a tidal fragment of the A+C
complex. The oxygen abundances in galaxies A and C are also understandable if
the A+C complex is a late-type spiral suffering strong gas inflow and star
formation as a result of a tidal interaction. Given the kinematics of both the
galaxies and the \ion{H}{i} gas, the oxygen abundances, and the position of
galaxy G, we propose that an interaction of galaxy G with the A+C complex,
rather than a merger of galaxies A and C, is a more complete explanation for
the tidal features and other properties of HCG31. In this case, the A+C complex
need not be a merger in progress, though this is not ruled out.
