This book gives a practical introduction to the B specification language and method, an approach to the development of high-quality software using rigorous CASE techniques.It is suitable for both undergraduate and postgraduate courses, in addition to being an introduction for industrial practitioners. Extensive examples of all development life-cycle stages are given, including animation, proof, design and code generation in C. Two large case studies and exercises with solutions are provided.The authors have extensive experience in teaching B and in its industrial application to high integrity systems. The book uses the B Toolkit to support the text, but it is also relevant to users of alternative toolsets for B.