Abstract
The Treaty of Timor Gap provides for a specific procedure of transboundary environmental impact assessment (EIA). However, the lack of consistency and coordination in implementing EIA, has reduced its effectiveness. Comparative studies of four EIA systems (including the Espoo convention) indicate their strengths and weaknesses in comparison with the Timor Gap process. Although there were clear procedures for EIA in Indonesia and Australia, incorporation of both systems into a transboundary EIA was not simple. Particular stages of the Timor Gap EIA system were inadequately implemented and the system needs to be improved. Lessons from the Timor Gap EIA will add knowledge about implementing transboundary EIA and are important for the future formulation of environmental regulations in the newly independent East Timor.