This book presents a comprehensive discussion on the field of distributed constraints, its algorithms and its active research areas. The well defined model of distributed constraints satisfaction and optimization (DisCSPs/DisCOPs) can serve as the basis for the design and investigation of distributed search algorithms, of protocols and of negotiations and search. The book introduces distributed constraint satisfaction and optimization problems and describes the underlying model. Presenting a complete state of the art in DisCSP and DisCOP research, the following topics are explored: - Families of search algorithms on DisCSPs and DisCOPs; - Distributed constraint optimization; - Ordering Heuristics for DisCSP algorithms; - Performance measures; - Impact of communication quality on distributed search; - Privacy issues; - Non exhaustive search algorithms on DisCSPs; - Applications of DisCSPs. This thorough exposition of the many elements of distributed search algorithms for DisCSPs and DisCOPs will be an invaluable read for both researchers and practitioners.