There is much interest in using complex-light modes for increasing the bandwidth of communications. Scalar modes have received much attention, but polarization modes may be more robust and effective. Superpositions of polarization and spatial modes of light create polarization patterns with topological disclination features. These patterns of polarization can be used in various ways to convey non-binary information. In this chapter we investigate the ways in which Poincaré modes, a type of spatially-variable polarization modes, can be used in communications.