The Galapagos Marine Reserve is one of the most recognized marine protected areas in the world, due mainly to its unique natural features. Little is known, however, about its social counterpart. This research aims to explore the Galapagos Marine Reserve governance by following the governability assessment framework, which is based on the interactive governance perspective. We claim that improved governance and incresed governability of this marine protected area, ruled under a co-management mode of governance, cannot be achieved without comprehensive understanding about the Galapagos Marine Reserve's governing system, the systems that are being governed, and their interactions. Semi-structured interviews with a range of stakeholders were conducted as part of the study to illuminate the characteristics of the systems and how they interact. The analysis reveals a high degree of variation between the formal and operative structures of the systems, due largely to the complexity, dynamics, and diversity of the systems, and the multiple scales at which they operate. Further, our findings highlight that governing decisions, and thus the overall governance performance, are influenced by certain quality of the systems (e.g., inefficiency, vulnerability, misrepresentation). Along with the understanding of potential complementarity with other governance modes (e.g., hierarchical), the research identifies that the governability of the Galapagos Marine Reserve can be improved by making governance processes more transparent and by better consideration of the social component in the governing system. In that way, the marine reserve sustainability would also be enhanced.