This article develops a framework for environmental policy analysis based on an encompassing assessment of transaction costs. This approach emphasizes the ex ante costs of establishing environmental entitlements, and the ex post costs of administrating, monitoring, and enforcing them. The framework is used to organize a literature review which addresses policy design and instrument choice, as well as optimal environmental policy-making and benefit-cost analysis. The review also considers the empirical literature on transaction costs associated with environmental policy-making, and current practices to record some categories of transaction costs in regulatory impact assessments. The article concludes with a discussion of the implications for environmental policy analysis.