The scope, complexity and interrelatedness of environmental problems presents a difficult challenge to policymakers. To date, public policies have been responsive largely to particular matters of public concern. They have typically been ad hoc, sectoral and segmental. Their administration has been charged to various agencies, each with its special mission. In consequence, governments have often acted to cross purposes; small results have often been ineffectual and, as often, unnecessarily expensive. Incremental innovation is seldom able to affect significantly the tendencies of the larger system of public policy and administration within which it is undertaken. Inasmuch as no country has had long experience with administration of environmental policy, a comparison of different approaches to environmental problems is useful. Direct transfers of method from one country to another may seldom be practicable, yet there may be lessons learned from the diverse experience of governments addressing similar problems. A comprehensive and radical institutional experiment in environmental policy has been initiated in the government of New Zealand. The New Zealand experiment may illuminate the effects of institutional structure on the implementation of policy. The relationships between constitutional principles, policy priorities and administrative structures have never been clear. The problems of coping with multiple environmental trends, their causes and their consequences justify efforts to find more effective methods of policymaking. Copyright 1993 by The Policy Studies Organization.