Eco-labels have been developed to face the difficulties faced by States in managing fisheries. They promote the voluntary adoption of sustainable practices, through market differentiation of sustainably produced items. In fisheries, the Marine Stewardship Council (MSC) is the most commonly used eco-label. The label is presumed to increase the social and political capitals of the certified fisheries. Mexico has the largest and longest experience in MSC within the developing countries. Mexico has had five certified fisheries including the first small-scale certified fishery. In this work we will focus on four of those five, also exploring the reasons that made 2 of these to withdrawn. The objective of this work is to explore non-financial economic benefits, associated to the certification of these fisheries. To this end, we did an stakeholder map to identify the key players of each certification process based on interviews and on-line MSC data. 40 interviews to those key players were done to recognize benefits associated with the certification. Despite the fact that half of the respondents acknowledge that there has been no improvement in the price of the product, two thirds stated that certification has allowed them to achieve better social or political agreements; around 80% would recommend certification. It is recognized that MSC's certification has not generated the financial returns expected, but it seems that it has resulted in other economical benefit, such as the validation of high social capital an the increasing of political capital.