  The rate of mass accumulation due to galaxy merging depends on the mass,
density, and velocity distribution of galaxies in the near neighborhood of a
host galaxy. The fractional luminosity in kinematic pairs combines all of these
effects in a single estimator which is relatively insensitive to population
evolution. Here we use a k-corrected and evolution compensated volume-limited
sample drawing about 300 redshifts from CFGRS and 3000 from CNOC2 to measure
the rate and redshift evolution of merging. We identify kinematic pairs with
projected separations less than either 50 or 100 \hkpc and rest-frame velocity
differences of less than 1000\kms. The fractional luminosity in pairs is
modeled as f_L(Delta v,r_p,M_r^{ke})(1+z)^{m_L} where [f_L,m_L] are
[0.14+/-0.07,0+/-1.4] and [0.37+/-0.7,0.1+/-0.5] for r_p<= 50 and 100\hkpc,
respectively (Omega_M=0.2, Omega_Lambda=0.8). The value of m_L is about 0.6
larger if Lambda=0. To convert these redshift space statistics to a merger rate
we use the data to derive a conversion factor to physical space pair density, a
merger probability and a mean in-spiral time. The resulting mass accretion rate
per galaxy (M_1,M_2>= 0.2 M*) is 0.02+/-0.01(1+z)^{0.1+/-0.5} M*~Gyr^{-1}.
Present day high-luminosity galaxies therefore have accreted approximately
0.15M* of their mass over the approximately 7 Gyr to redshift one. (abridged)
