Nuclear-explosive prompt diagnostics techniques and equipment are surveyed. These techniques and equipment have been developed to answer nuclear-explosive performance questions. The techniques and equipment must be selective in radiation sensitivity, linear in calibration, fast, insensitive to strong signals, wide in dynamic range, and reliable. Diagnostic techniques and equipment measure neutron, gamma-ray, and x-ray emissions, as well as aid in the determination of the physical location of the production of radiation through imaging. The high cost of nuclear experiments will continue to encourage the development of sophisticated techniques to gain as much information as possible from each experiment.