This program involves experimental and theoretical investigations of low-temperature plasmas and is continually evolving as new applications and directions are found. Some of these plasmas are in thermodynamic equilibrium while others are clearly nonequilibrium plasmas. For the experimentalist, in situ laboratory diagnostics range from incredibly sophisticated to elegantly simple, as low-temperature plasma research requires a variety of approaches in identifying critical quantities. For the theorist, the challenges range from interpretation of experimental results to providing direction for future experiments. Theoretical efforts also focus on gaining a predictive capability in parameter regimes that may not be accessible in the laboratory. Current efforts include plasmas associated with materials processing and space physics, afterglow plasmas, dusty plasmas, and negative ion plasmas. A strong emphasis is placed on real applications usually consisting of multiple gases and/or particulates, which give rise to numerous ion and radical species. This program is interdisciplinary and collaborative.