Defined as the benefits derived from nature to humans, the Ecosystem Services (ES) concept clarifies how ecosystems contribute to human well-being. Despite its relevance, integrating this concept into decision-making processes remains a challenge. Participatory approaches have proven crucial in developing mechanisms for managing, conserving, sustainably using and valuing ES. This work aimed to analyse the perceptions of Portuguese Biosphere Reserves’ (BR) managers regarding the ES provided by these territories through a participatory workshop. During the workshop, each participant specified the most relevant ES provided by the BR. The study identified three key ES: "Cultivated terrestrial plants (including fungi, algae) grown for nutritional purposes", "Characteristics of living systems that enable scientific investigation or the creation of traditional ecological knowledge" and "Characteristics of living systems that enable education and training". Additionally, participants discussed perceived threats, opportunities and potential solutions to enhance the value of these key ES in these areas. "Climate change" and "Pollution" were identified as the most significant threats, while "Climate adaptation", "Quality of life" and "Sustainable agriculture" emerged as the main opportunities. Solutions to address threats and maximise opportunities include the establishment of a closer, systematic and articulated relationship within BR to promote sustainability and resilience. Overall, the workshop was positively evaluated and deemed productive. It was also considered a powerful tool to foster collaboration towards a more holistic promotion of BR' sustainable governance, benefitting the environment, communities and the economy.