OIKOS is an association dedicated to protecting the environment and heritage of the Leiria region. Its work includes environmental education, public engagement, and initiatives that encourage people to understand and care for local natural resources. A key initiative is the Lis River Basin project, “Act to Understand, Protect and Value,” which runs from the 2024/2025 to the 2026/2027 school years. The project develops environmental education for sustainability, drawing on Portugal’s sustainability education and citizenship frameworks, national environmental education goals, and the United Nations Sustainable Development Goals. It has institutional support from the Directorate-General for Education, the Directorate-General for School Establishments, the Portuguese Environment Agency, and the Institute for Nature Conservation and Forests.

OIKOS also organizes congresses, conferences, colloquia, technical courses, projects, and other activities, and produces publications. The association shares communications and opinions on environmental matters and provides information about its work and governance. Its activities rely on volunteer contributions, and supporters can help by assigning 1% of their assessed personal income tax collection to OIKOS, at no additional cost.