High-capacity intersatellite communication crosslinks will allow more efficient and reliable operation of military and commercial satellite systems. High-speed optical crossl inks can serve as a key building element of an interconnected space-based communication systemfor military applications. A network such as this would provide immediate communication among satellites, eliminating the need for ground-based relay stations and expensive worldwide ground tracking networks, which would greatly improve the efficacy and reduce the vulnerability of existing satellite systems. Crosslinks can also provide connectivty for commercial global satellite communication systems and for deep-space applications. Optical heterodyne communicatiol systems using semiconductor lasers offer small-aperture, modest-weight, low-power, point-to-point crosslink packages, characteristics that are suitable for the envisioned applications. System research and development performed at Lincoln Laboratory permits the implementation of an efficient optical crosslink based on readily available, state-of-the-art devices and technology.