Recent success stories demonstrated that the combination of subcellular prefractionation methods with proteomic analysis is a very potent approach to simplify complex protein extracts from cells or tissues and to detect low abundance proteins. It also made clear that sophisticated strategies encompassing sample preparation, analytics and validation steps were required to fully exploit the potential of subcellular proteomics.This volume summarizes the new developments that made subcellular proteomics a rapidly expanding area. It examines the different levels of subcellular organization and their specific methodologies. In addition, the book includes coverage of systems biology that deals with the integration of the data derived from these different levels to produce a synthetic description of the cell as a system.