Abstract: Wave vector division multiplexing (“WVDM”) is a method of free-space multiplexing for optical communications. In WVDM, wave vectors of individual laser beams are manipulated so that each individual laser beam has a unique wave vector. These individual laser beams are multiplexed into an aggregate beam, which is transmitted to a receiver. The receiver separates the individual laser beams on the basis of their unique wave vectors. One area where WVDM is useful is in quantum cryptography. WVDM can also be combined with traditional wavelength division multiplexing (“WDM”) to increase throughput even further.