The Formal Aspects of Computing Science (FACS) Specialist Group of the British Computer Society set up a seriesof evening seminarsin 2005to report on advances in the application of formal design and analysis techniques in all the stages of software development. The seminars attracted an audience fromboth academiaand industry, andgavethem the opportunity to hear and meet pioneers andkeyresearchersin computing science.Normally it wouldbe necessaryto travelabroadand attend an internationalconference to be in the presence of such respected ?gures; instead, the evening seminar programme, overa period of threeyears,broughtthe keynotespeakers of the conference to theBritishComputerSocietyheadquarters,fortheconvenienceofanaudience basedinLondon.Severalspeakersfromtheperiod2005-2007kindlydeveloped their talks into full papers, which form the basis of this volume. Iamdelightedtowelcomethepublicationofsuchanexcellentandcomp- hensiveseriesofcontributions.Theyarenowavailableinbookformtoaneven wider audience, including developers interested in solutions already available, and researchers interested in problems which remain for future solution. Sir Tony Hoare Preface They envy the distinction I have won; let them therefore, envy my toils, my honesty, and the methods by which I gained it. - Sallust (86-34 BC) Formalmethods area powerfultechniqueforhelping toensure the correctness of software. The growth in their use has been slow but steady and they are typically applied in critical systems where safety or security is paramount.