A number of diagnostics utilizing the radiation emitted from high-temperature plasmas have been developed at Los Alamos. Photoemissive x-ray diodes with photon energy bandpass filters provide time-resolved rough spectral data from about 6 eV to >10 keV photon energy. Filtered silicon photodiodes can be used down to 1 eV and offer the advantages of nominally flat response and ability to operate in poor vacuum conditions. Both types of diodes will provide a rough time-resolved spectrum and both are relatively inexpensive, reliable, and passive (i.e., no synchronization problems). For higher-energy resolution, bent crystal spectrographs are used in the x-ray region. With the addition of streak cameras or gated microchannel plates these systems provide data with high energy and high time resolution. To measure the total energy output, a thin foil bolometer is used that measures the change in foil resistance as it is heated by the plasma radiation. By combining these diagnostics into a complementary set good diagnostic information can be guaranteed on any plasma experiment.