  WR+O star binary systems exhibit synchrotron emission arising from
relativistic electrons accelerated where the wind of the WR star and that of
its massive binary companion collide - the wind-collision region (WCR). These
``colliding-wind'' binaries (CWB), provide an excellent laboratory for the
study of particle acceleration, with the same physical processes as observed in
SNRs, but at much higher mass, photon and magnetic energy densities. WR140 is
the best studied CWB, and high resolution radio observations permit a
determination of several system parameters, particularly orbit inclination and
distance, that are essential constraints for newly developed models of CWBs. We
show a model fit to the radio data at orbital phase 0.9, and show how these
models may be used to predict the high energy emission from WR140.
