We report the simultaneous monitoring of the environment-state and wafer-state during epitaxial crystal growth using a single real-time measurement. Atomic absorption spectroscopy (AAS) is used to monitor the incident molecular beam flux while UV reflectance (UVR) at 396 nm with an incident angle of 78° is used to monitor growth on the wafer. We have studied the utility of AAS/UVR monitoring of AlxGa1-xAs deposition: AlAs growing on GaAs, GaAs on AlAs, and superlattice growth. Additionally, optical multichannel spectroscopy (OMS) data were acquired throughout the growth of a distributed Bragg reflector (DBR). The relationship of the structure of the real-time OMS data to absorption, optical path length variation, and differential layer thickness variations is also discussed. Numerical simulations of the real-time wafer-state monitors using pseudodielectric constants, appropriate at a growth temperature of 579 °C, show good agreement with measured spectra.