New Zealand established a position of environmental leadership throughout the negotiations on the Protocol. New Zealand’s performance in environmental leadership since then was assessed under the Antarctica (Environmental Act) 1994 and in its contribution to the Committee on Environmental Protection (CEP). The Antarctic Treaty Secretariat database was used to retrieve information on the number of Environmental Impact Assessments approved. New Zealand’s performance was then measured by the compliance of its Crown Entity, Antarctica New Zealand with the conditions of its approval which covered the operation of Scott Base and all field events supported by Antarctica New Zealand. This showed only minor non-compliances with less than minor impact. The number of Initial Environmental Evaluations was benchmarked against other countries and showed New Zealand received substantially more than every other party except the United States. New Zealand’s international contribution was measured by its contribution to comments on Comprehensive Environmental Evaluations (CEE) and on the number of Working Papers submitted to the CEP. New Zealand is one of a few countries regularly submitting on CEEs and submits more Working Papers than every party except the United Kingdom. When normalised by the GDP New Zealand stands out in its engagement with the CEP. 3 Case studies are used to provide more detailed examination.