Models of the non-thermal emission from early-type binaries

The powerful wind-wind collision in massive star binaries creates a region of high temperature plasma and accelerates particles to relativistic energies. I briefly summarize the hydrodynamics of the wind-wind interaction and the observational evidence, including recent $\gamma$-ray detections, of non-thermal emission from such systems. I then discuss existing models of the non-thermal emission and their application to date, before concluding with some future prospects.