Small islands provide an opportunity to influence the debate on Strategic Environmental Assessment (SEA) towards sustainability, due to their specific natural and human features. The research goal was to understand how sustainability might be advanced through SEA in small islands, supported by the development of a conceptual framework and recommendations for its implementation. The framework developed provides for the identification of clusters of concepts linking SEA with sustainability in small islands, identified as being key actors, island cooperation and information exchange networks, and small islands SEA-specific issues. These clusters of concepts are interlinked through the actors in a continuous loop of learning and improvement process. The implementation of the framework is recommended based on different key factors, which derived from the conceptual framework: awareness for decision-makers; empowerment and ownership of practitioners and intermediate decision-makers; small islands cooperation and exchange networks; SEA specific issues for small islands; and, small islands specific stakeholders' engagement (local knowledge). The application of the framework developed was conceptualized for the Azores and Orkney archipelagos due to their well-established SEA systems, with similar legal background – the European Union SEA Directive (Directive 2001/42/EC). In the Azores, the SEA system may promote an easier transition towards new models of thinking, but more challenges are expected for Orkney practitioners and decision supporters which may need to use creative solutions to overcome them. Overall, this research concludes that a mind-set changing capacity is needed, enhancing future practice and influencing different stakeholders for the need of specific small islands approaches. The proposed framework should be adopted as a dynamic tool and adjusted iteratively with practice.