Diffusion and interdiffusion in GaAs and GaAs/AlGaAs superlattices are shown to be consistent with the charged point‐defect model. The charged Ga vacanciesV3−Gaand interstitialsI2+Gaappear to control group II, III, and probably V element diffusion. After adjustment for carrier concentration and As pressure, these elements are found to have a nearly identical intrinsic diffusivity and activation energy over a wide range of temperature. A natural consequence of Ga diffusion via negative or positive point defects is that enhanced group‐III interdiffusion is expected with eithern‐ orp‐type doping. Anomalous enhancements in group‐II dopant diffusivity have been related to the supersaturation of Ga interstitials.