This book constitutes the refereed proceedings of the 8th International Conference on Integrated Formal Methods, IFM 2010, held in Nancy, France, in October 2010. The 20 revised full papers presented together with 3 invited papers were carefully reviewed and selected from 59 submissions. The papers address the spectrum of integrated formal methods, ranging from formal and semiformal notations, semantics, refinement, verification and model transformations to type systems, logics, tools and case studies.