Contact mechanics was and is an important branch in mechanics which covers a broad field of theoretical, numerical and experimental investigations. In this carefully edited book the reader will obtain a state-of-the-art overview on formulation, mathematical analysis and numerical solution procedures of contact problems. The contributions collected in this volume summarize the lectures presented during the 4^th Contact Mechanics Interantional symposium (CMIS) held in Hannover, Germany, 2005, by leading scientists in the area of contact mechanics.