Sustainability: economic sustainability, ecologic sustainability and what are the institutional arrangements that manage to reconcile these two objectives over time. The study of the governance of common pool natural resources could represent an important tool to understand the complexity of interactions between ecological and socio-economic spheres. This paper aims to achieve several goals. Firstly, is to contribute to natural resource governance literature from the perspective of institutional environmental economics. More specifically, it will contribute to the common pool resources (CPR) theories by broadening the scope to the context in which they are embedded. Secondly it will focus specifically on marine natural resources, via two spatial interconnected case studies: the marine protected areas and the harvesting of the invasive species Rapana Venosa in the Bulgarian Black Sea. Thus, trying to determinate the institutional level challenges and explore the potential path of institutional arrangements for the governance of those resources.