The metalorganic chemical vapor deposition (MOCVD) process for electronic and photonic compound semiconductor materials and devices is reviewed. We begin with an introduction to the basic MOCVD chemical reaction process, gas delivery equipment, reaction chambers, and safety. Growth mechanisms including hydrodynamics, boundary-layer issues, thermal effects, and pyrolysis reactions, are defined, and criteria for growth regimes, growth rate, and alloy composition are described Material, structural, and dopant considerations, which are particularly important to optoelectronic devices, are presented. Last, a brief description of the selective area epitaxial growth process is presented.