This volume contains the proceedings of iFM 2010, the 8th International Conference on Integrated Formal Methods. The conference took place during October 12-14, 2010, at the INRIA research center and the LORIA laboratory in Nancy, France. Previous editions were held in York, Dagstuhl, Turku, Canter- bury, Eindhoven, Oxford, and Düsseldorf. The iFM conference series seeks to promote research into the combination of different formal methods, and of formal and semi-formal methods, for system development. Such combinations are useful in order to apprehend different aspects of systems, including functional correctness, security, performance, and fault-tolerance. The conference provides a forum for discussing recent advances in the state of the art and for disseminating the results among the academic and industrial community.