The use of chemical weapons may have started with World War I, but as a result of the armed conflicts in the Middle East the monitoring of chemical production has gained an unprecedented immediacy. This volume is the first comprehensive analysis of on-site test inspections conducted in the chemical industry. These inspections helped to design and test the verification mechanisms for future international Chemical Weapons Conventions. The author analyzes these inspections to predict future inspection methods. He also describes problems encountered and proposes improvements to increase the efficiency of the verification system.