This book constitutes the refereed proceedings of the 5th International Conference on Integration of AI and OR Techniques in Constraint Programming for Combinatorial Optimization Problems, CPAIOR 2008, held in Paris, France, in May 2008.

The 18 revised long papers and 22 revised short papers presented together with 3 invited talks were carefully reviewed and selected from 130 submissions. The papers describe current research in the fields of constraint programming, artificial intelligence, and operations research to explore ways of solving large-scale, practical optimization problems through integration and hybridization of the fields' different techniques.