This paper presents an empirical analysis of the Japanese coastal fishery co-management system. In particular, the paper focuses on the effectiveness of Fishery Management Organizations (FMOs), which are established by groups of fishermen and set rules and regulations that they self-enforce. The paper finds that FMOs engaged actively in marketing practices in their output markets significantly increased their member fishermen's revenue. Proceeds sharing rules, where individual proceeds are pooled and shared among the members, appeared to have marginal effects despite of several anecdotal evidence that suggests otherwise. Findings suggest that benefit gains from the output markets is substantial in successful fishery co-management.