Visitors to publicly owned national parks, wildlife reserves and other natural areas pay entrance fees and other charges for their access and use. What principles and criteria contribute to an appropriate pricing policy? The answers to this are complex because of multiple pricing objectives, visitor categories, visitor activities, fee instruments and philosophical positions. In this review paper, these issues are examined from the perspective of public agencies that are working to improve their pricing practices. Pricing is a potentially powerful tool to move towards greater efficiency, fairness and environmentally sustainable management. To date, this tool is underutilized.