Soft x-rays span the region between x-ray and UV, with energies from approximately 10 to 100 Å (0.12 – 1.2 keV). This range of energies is particularly interesting for x-ray spectroscopy. Important applications include x-ray astronomy and metrology of high-energy plasmas (for example, spectroscopy and imaging with x-rays provides information on the composition and behavior of plasmas as a function of time and position). Soft x-rays also have potential use in next-generation surface inspection and material characterization tools. In these applications, the critical optical element is a high quality crystal with suitable interplanar spacing to permit diffraction and focusing of soft x-rays. Inrad Optics offers several crystals suitable for soft x-ray applications, including KAP and RbAP. These crystals can be supplied either flat or bent to a prescribed radius of curvature.