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.

This book constitutes the refereed proceedings of the 7th International Conference of B Users, B 2007, held in Besançon, France in January 2007. The 30 revised full papers presented together with 4 invited contributions were carefully reviewed and selected from numerous submissions. The topics of interest to the conference included: industrial applications and case studies using B, integration of model-based specification methods in the software development lifecycle, derivation of hardware-software architecture from model-based specifications, expressing and validating requirements through formal models, in particular verifying security policies, theoretical issues in formal development, model-based software testing, tools supporting the B method, development by composition of specifications, validation of assembly of COTS by model-based specification methods, B extensions and/or standardization.