Institutional and non-institutional factors for the success of protected area (PA) governance have repeatedly been identified, but their relative weight has not been evaluated. To investigate the implementation of PA management in Zakynthos (Greece), meeting minutes of the local Park Authority for its first four years of operation were reviewed and statistically analysed. The Park Authority's autonomy and management complexity were indicated and with reference to governance, members of the local Park Authority belonged to the ‘inner-circle’ of decision-making and the Ministry of Environment formed the ‘environment’, since administrative issues had to be approved by the latter. Implementation of actions referring to administrative issues was less likely than implementation of environmental, social and economic arrangements, where the Park Authority had a higher degree of autonomy. The implementation of arrangements for promoting administrative stability and viability was highly dependent on external actions (annual government funding and approval of by-law governance and implementation). The more sophisticated and complex the governance system became, the more likely it was that Park Authority encountered difficulty when trying to make choices and changes. The methodology proved effective in revealing the management behaviour of the Park Authority, as well as indicating institutional and non-institutional issues that most significantly affected the harnessing of resources and the degree of action implementation; this could offer crucial feedback to managers and governmental representatives on the factors responsible for the success or failure of PA management.