Fuel cells are devices that convert chemical energy into electrical energy. In this volume, Sadiq Al-Baghdadi (mechanical engineering, International Technological University, London) discusses proton exchange membrane fuel cells (the PEM of the title). It is claimed that this type of fuel cell, one of many, promises several advantages as a power system of the future for portable electronic applications: compact and light weight, efficient at low temperatures with high output power density, and offering good start up and shut down. This text then presents mathematical modeling and computer simulation (CFD) material that should advance design in this field. A table of nomenclature is provided and figures appear on nearly every page. Annotation ©2010 Book News, Inc., Portland, OR (booknews.com)