Increasing use of marine protected areas for pursuits such as recreational scuba diving may lead to biological damage and reduced amenity values in popular locations. The relationships between biological and amenity values are discussed and the work of Dixon et al. (1993, Meeting ecological and economic goals: marine parks in the Caribbean. Ambio 22, 117-125) on allocating divers between sites is extended. It is concluded that the carrying capacity concept and the critical thresholds approach are constrained by a number of limitations on their effectiveness as resource management tools. The optimal allocation of users between recreational dive sites is, subsequently, examined and the potential application of economic instruments to achieve such an allocation is assessed. It is concluded that a judicious blend of regulation and the use of economic instruments will be required to overcome open access and boundary problems, and will provide for better overall management of popular marine recreational sites than is presently the case. Education will also have a significant role to play by increasing environmental awareness and reducing the damaging impacts caused by users of those popular sites.