Invited Talks -- E-Voting and the Need for Rigourous Software Engineering – The Past, Present and Future -- Using B Machines for Model-Based Testing of Smartcard Software -- The Design of Spacecraft On-Board Software -- Regular Papers -- Interpreting Invariant Composition in the B Method Using the Spec# Ownership Relation: A Way to Explain and Relax B Restrictions -- Chorus Angelorum -- Augmenting B with Control Annotations -- Justifications for the Event-B Modelling Notation -- Automatic Translation from Combined B and CSP Specification to Java Programs -- Symmetry Reduction for B by Permutation Flooding -- Instantiation of Parameterized Data Structures for Model-Based Testing -- Verification of LTL on B Event Systems -- Patterns for B: Bridging Formal and Informal Development -- Time Constraint Patterns for Event B Development -- Modelling and Proof Analysis of Interrupt Driven Scheduling -- Refinement of Statemachines Using Event B Semantics -- Formal Transformation of Platform Independent Models into Platform Specific Models -- Refinement of eb 3 Process Patterns into B Specifications -- Security Policy Enforcement Through Refinement Process -- Integration of Security Policy into System Modeling -- Industrial Papers -- Experiences in Using B and UML in Industrial Development -- B in Large-Scale Projects: The Canarsie Line CBTC Experience -- A Tool for Firewall Administration -- The B-Method for the Construction of Microkernel-Based Systems -- Hardware Verification and Beyond: Using B at AWE -- Tool Papers -- A JAG Extension for Verifying LTL Properties on B Event Systems -- A Generic Flash-Based Animation Engine for ProB -- BE4: The B Extensible Eclipse Editing Environment -- BRAMA: A New Graphic Animation Tool for B Models -- LEIRIOS Test Generator: Automated Test Generation from B Models -- Meca: A Tool for Access Control Models -- JML2B: Checking JML Specifications with B Machines -- Invited Talk -- Plug-and-Play Nondeterminacy.

TheseproceedingsrecordthepaperspresentedattheSeventhInternationalC- ference of B Users (B 2007), held in the city of Besan¸ con in the east of France. This conference was built on the success of the previous six conferences in this series, B 1996, held at the University of Nantes, France; B 1998, held at the University of Montpellier, France; ZB 2000, held at the University of York, UK; ZB 2002, held at the University of Grenoble, France; ZB 2003, held at the U- versity of Turku, Finland; ZB 2005 held at the University of Surrey, Guildford, UK. B 2007 was held in January at the University of Franche-Comt´ e,Besan¸ con, France, hosted by the Computer Science Department (LIFC). LIFC has always placed particular emphasis on the applicability of its research and its relati- ship with industrial partners. In this context, it created in 2003 a company called LEIRIOS Technologies, which produces an automatic test generator tool (LTG) frommodels described in the B speci?cationlanguage. Other members of LIFC work on extensions of the B method for specifying and verifying dynamic properties. All the submitted papers in these proceedings were peer reviewed by at least three reviewers drawn from the B committee, depending on the subject matter of the paper. The authorsof the papersforB 2007werefrom Australia,Canada, Finland, Germany, France, Switzerland, and the UK. The conference featured a rangeof contributions by distinguished invited speakers drawn from both ind- try and academia.