The design and implementation of ecologically effective marine protected areas (MPAs) are influenced by social acceptance and the impact of MPAs on communities. Integrative analyses of the social and ecological determinants of marine conservation efforts and MPA networks are lacking but are needed to achieve desired outcomes. We developed and applied a "socialecological well-being" (SEWB) approach to critically examine the linkages between MPAs and well-being in Southwest New Brunswick (Bay of Fundy, Canada). SEWB is defined as a social-ecological system state in which ecological resilience is sustained, while human needs are met and the quality of life of individuals is maintained. We examined (1) how stakeholders perceive benefits and costs of MPAs in relation to SEWB, and (2) how well-being insights contribute to the effectiveness of MPA governance. Using a qualitative case study approach, we conducted 49 semistructured interviews and 4 focus groups with fishers and other key informants at an existing MPA, as well as at an ecologically and biologically significant area that is a candidate for a future MPA. We identified 15 attributes of SEWB that related to MPAs, such as fishery access, community relations, place identity, and natural capital. Three key governance insights for decision makers emerged from the identification of these attributes: (1) displacement attributable to MPAs has implications across material, relational, subjective, and ecological dimensions; (2) effective collaboration is critical for community support, but perspectives about what constitutes effective collaboration may vary across stakeholder groups; and (3) aspects of MPA design fit poorly with the local context because they do not take social and ecological dynamics into account. Our findings empirically demonstrate the applicability of the SEWB framework, suggest a need to focus more on governance processes and improving fit, and highlight barriers to aligning national and local conservation priorities.