In 2003, by endorsing the Guiding Principles for Reform of Environmental Enforcement Authorities in Transition Economies, the countries of Eastern Europe, Caucasus, and Central Asia (EECCA) agreed on a reference model to guide the modernisation of their systems for environmental regulation and compliance assurance. This report reviews their progress in implementing the Guiding Principles. The main conclusion is that countries took action to comply with the Guiding Principles, mostly to elevate the status of environmental enforcement authorities, clarify responsibilities, and provide training and a better infrastructure. While such improvements are an important basis for further reform, continued lack of progress in modernising strategies and instruments of work will inhibit institutional and environmental performance.