This is the 5th edition of the International Conference on Integrated Formal Methods (IFM). Previous IFM conferences were held in York (June 1999), D- stuhl (November 2000), Turku (May 2002) and Canterbury (April 2004). This year s IFM was held in December 2005 on the campus of the Technische Univ- siteit Eindhoven in The Netherlands. This year IFM received 40 submissions, from which 19 high-quality papers wereselectedbytheProgramCommittee.Besidesthese, theproceedingscontain invited contributions by Patrice Godefroid, David Parnas and Doron Peled. It was 10 years ago that Jonathan P. Bowen...