  We derive basic scaling equations for relativistic magnetic reconnection in
the general case of asymmetric inflow conditions and obtain predictions for the
outflow Lorentz factor and the reconnection rate. Kinetic Particle-in-Cell
simulations show that the outflow speeds as well as the nonthermal spectral
index are constrained by the inflowing plasma with the weaker magnetic energy
per particle, in agreement with the scaling predictions. These results are
significant for understanding non-thermal emission from reconnection in
magnetically-dominated, astrophysical systems, many of which may be asymmetric
in nature. The results provide a quantitative approach for including asymmetry
on reconnection in the relativistic regime.
