Regions and countries manage and sustain oceanic resources and services with varying degrees of success. Our empirical analysis discusses the extent to which this variation can be explained by common-pool resource (CPR) characteristics, controlling for institutional quality, island status, the existence of marine-protected areas, and the ratification of marine environmental agreements. Using data from the Ocean Health Index (OHI), we confirm that the problems related to CPRs are not restricted to fisheries. Other oceanic services and assets, including the provision of oceanic natural products, habitat health, and species richness, also decline with the number of neighboring countries. By contrast, the aspects of ocean health-like sustainable tourism, the preservation of iconic species, or the mitigation of trash pollution benefit from neighborhood stress. Overall, there is little evidence that economic development (expressed in per capita gross domestic product [GDP] and used as a proxy for institutional quality) contributes to sustaining oceanic resources. In general, the OHI appears to capture the established characteristics of various oceanic resources and services very well. Accordingly, it represents an important data source for improving our understanding of the variation in oceanic resources and services, an indispensable factor in developing and achieving sustainable development strategies for the ocean.