Radiation detectors are used to detect energetic ionizing radiation due to such quanta as: gamma rays, x-rays, protons, alpha particles, neutrons and beta particles (electrons and positrons). Radiation-detector technologies span a wide range of applications of benefit to mankind. Examples include: medical imaging, biomedical research, nuclear safeguards, and nonproliferation, explosives detection and threat reduction, nondestructive testing, and materials research. Energetic ionizing radiation presents unique challenges to the designers of components and systems, due to the nature of its interactions with matter. This conference provides an interdisciplinary forum for detector-materials developers, instrument designers and users to report on recent results, improvements, and new approaches for using ionizing radiation. Emphasis is on new detector materials, novel applications and imaging. Please note, this conference previously had the title: "Penetrating Radiation Systems and Applications," the name change should foster better alignment with conventional terminology.