The book gives a broad presentation in laymen's language of the creation and the implementation of the treaty prohibiting nuclear test explosions (Comprehensive Nuclear-Test-Ban Treaty: CTBT), one of the key guarantors of nuclear non-proliferation. The writers, who personally guided this work for more than 25 years, give a unique insight into the challenging international work to establish a complex technological system with global coverage in a political environment.

Extensive nuclear testing has occurred and this is comprehensively reviewed, as are the arguments in favour of a test ban and efforts to implement one. The Conference on Disarmament in Geneva witnessed unprecedented efforts by scientists from around the world to form a common understanding of how to verify a test ban treaty and develop a prototype global verification system; work that was significant in building confidence at the height of the Cold War. The political negotiations and Treaty itself are briefly analysed, but the main part of the book is devoted to more than a decade of effort by the Preparatory Commission for the CTBT Organization to implement the treaty and its verification system: the most comprehensive verification system ever created, with a global coverage connecting more than 300 monitoring stations and an intrusive on-site inspection regime.

The first, most promising test results are also presented. An essential element of the book is its assessment of the experience gained through many years of political, managerial and technical activity. Such lessons, if well learned, can benefit the negotiations of future international treaties where verification is crucial, such as in arms control, disarmament or the environment.

Audience: This book will be of interest to professionals in political, diplomatic and military areas, and to politicians and their staffs. Scientists and graduate students in political science and researchers at institutions in security related fields and at NGOs will find valuable information in this book.

Zusammenfassung
Nuclear tests have caused public concern ever since the first such test was conducted, more than six decades ago. During the Cold War, however, con- tions were not conducive to discussing a complete ban on nuclear testing. It was not until 1993 that negotiations on such a treaty finally got under way. From then on, things moved relatively quickly: in 1996, the United Nations General Assembly adopted the Comprehensive Nuclear-Test-Ban Treaty (CTBT). To date, the Treaty has been signed by 178 states and ratified by 144, though it has yet to enter into force, as nine out of 44 ''Annex 2 states'', whose ratification is mandatory, have not heeded the call. Nevertheless, the CTBT verification system is already provisionally operational and has proven its effectiveness. We commend the CTBT organisation in Vienna for its successful efforts to build a verification network. This book is an excellent overview of the evolution of the CTBT and its verification regime. The authors are eminent scholars from the Netherlands, Norway and Sweden who have been intimately involved with the CTBT and its verification agency, the CTBTO Preparatory Commission, from their inc- tion to the present day. They have written a thorough and engaging narrative of the long road that led to the CTBT. Their story will appeal to both the layman and the expert and provide useful lessons for future negotiations on disarmament issues.

Inhalt
To Test or Not to Test.- Monitoring Technologies.- A Long Journey to a Treaty.- The Treaty.- The Birth of An Organization.- Establishing the Verification Regime.- Testing Shows High Performance.- National Technical Implementation of the CTBT.- The CTBTO Preparatory Commission and the PTS - an Organizational Perspective.- The CTBTO Preparatory Commission and the World.- Always Too Early to Give Up.