When cells are damaged, as often occurs during trauma and metabolic stress, a highly evolved cell healing process follows that was designed to enhance cell survival or remove irreparably injured cells. Following injury, cells attempt to seal breaks in their membranes, chaperone removal or refolding of altered proteins, repair damaged DNA, or if necessary commit to programmed cell death. When cell injury is too extensive to permit reparative responses, acute cellular necrosis or apoptosis can result. Understanding injury at the subcellular organelle and molecular levels is essential for development of new therapeutic strategies and for optimal management of injured victims. In this volume, various modes of injury that can occur are described, as well as the basic molecular healing responses and pathways of metabolic survival or death. The approach taken here is to look at these processes at the cellular and subcellular levels, rather than at the tissue level, and this volume will be a valuable resource to anyone interested in wound healing, biological stress responses, molecular chaperones, radiobiology, biomechanics, and biomedical engineering, as well as trauma and critical care medicine.