Eco-Schools is an international programme run by the Foundation for Environmental Education and developed in Portugal since 1996 by the Blue Flag Association for the Environment and Education (ABAAE). This programme encourages action and recognises the quality work carried out by schools in the field of environmental education and education for sustainable development, providing methodology, training, teaching materials, support and a framework for the work carried out by schools.

In Seixal, the city council has been supporting this programme in the municipality's public and public schools since the 1998-1999 school year, entering into an annual partnership with ABAAE to implement the project in the schools that sign up.