Ultraviolet LEDs and solar blind detectors represent the next frontier in solid state emitter technology, holding out the prospect of many major applications, including the identification of hazardous biological agents. The current work draws together leading researchers in UV semiconductor technology and systems applications. Topics covered include basic device issues, substrates, epitaxial growth, materials characterization, nitride quaternary alloys, doping, strain energy band engineering, quantum phosphors, ohmic contacts and Schottky barriers, UV LED device design and performance, thermal management, and applications such as hazardous agent sensing, solid state lighting, environmental control, and optical measurement.