This study focuses on understanding stakeholder perceptions in environmental governance and management. Based on an application of the net-mapping method as the main approach for a comparative analysis of local ecosystem users' perceptions, this research elucidates subjective local realities of fishers and tourism operators in two study sites of the governance system of a marine protected area in Northeast Brazil. The findings showed that fishers and tourism operators see themselves as part of specific webs of social relations with associated power asymmetries. The perceived governance interaction networks varied between stakeholder groups, since they see reef governance in relation to their own interests and vulnerabilities. These variations in perception set the scene for different actions. The results of this comparative study show that where ecosystem users perceived the environmental rule system to be equitable and legitimate, its implementation was enhanced, where they did not, it was fraught with difficulties. This points to the potential for applying a systematic approach for differentiating perceptions, and their change over time, as behavioural drivers to strengthen future sustainability research. The article concludes with reflections on net-mapping as a tool for analysing perceptions on environmental governance.