  A renormalization group treatment of metamagnetic quantum criticality in
metals is presented. In clean systems the universality class is found to be of
the overdamped, conserving (dynamical exponent z=3) Ising type. Detailed
results are obtained for the field and temperature dependence of physical
quantities including the differential susceptibility, resistivity and specific
heat near the transition. An application of the theory is made to Sr3Ru2O7,
which appears to exhibit a metamagnetic critical end-point at a very low
temperature and a field of order 5-7T.
