Ensuring continuous compliance to environmental regulations is an important task for agencies charged with maintaining healthy ecosystems over the long term. Unfortunately, environmental agencies with very limited resources are commonly required to monitor discharges from many facilities, to assess apparent violations, and to carry out enforcement actions as appropriate. Moreover, relatively small penalties are the norm for most convictions, so deterrence by the threat of heavy fines is rarely practical. The overall objective of this project is to develop a general methodology for assessing the viability and effectiveness of various approaches to the enforcement of environmental laws and regulations. More specifically, the methodology is based on the game-theoretic models of verification theory, economics, statistical techniques, monitoring and risk management. The effectiveness of enforcement policies is assessed in terms of factors such as the private gain for violations, the costs of inspection, the structure and levels of penalties, the social costs of violations, and the social value of compliance.