The scientific career of John Stewart Bell was distinguished by its breadth and its quality. He made several very important contributions to scientific fields as diverse as accelerator physics, high energy physics and the foundations of quantum mechanics. This book contains a large part of J S Bell's publications, including those that are recognized as his most important achievements, as well as others that are for no good reason less well known. The selection was made by Mary Bell, Martinus Veltman and Kurt Gottfried, all of whom were involved with John Bell both personally and professionally throughout a large part of his life. An introductory chapter has been written to help place the selected papers in a historical context and to review their significance. This book comprises an impressive collection of outstanding scientific work of one of the greatest scientists of the recent past, and it will remain important and influential for a long time to come.