The central theme of the RLE Optical and Quantum Communications Group has been to advance the understanding of optical and quantum communication, radar, and sensing systems. Broadly speaking, this has entailed: (1) developing system-analytic models for important propagation, detection, and communication scenarios; (2) using these models to derive the fundamental limits on system performance; and (3) identifying, and establishing through experimentation the feasibility of, techniques and devices which can be used to approach these performance limits.