Social participation is nowadays a pre-requisite for development. Its importance resides in the capacity of the different social participants to organize themselves in order to fully exercise their citizenship and improve the quality of their lives.

In this way, it is possible to foresee a development process detached from imposed models which results from the actual participation of the community. It is the society itself that should identify and attain the satisfaction of its needs, through its representatives and its government.

The Agenda 21, prepared after the Rio Summit, in 92, was designed as a participation tool accessible to all and adaptable to the characteristics and peculiarities of each social group.

The 1992 United Nations Conference on Environment and Development, known as Rio-92, represented an international conference attended by heads of state and official representatives of 178 countries, and where NGOs (Non Governmental Organizations) from all over the world met in one single event - The International Forum for NGOs and Other Social Movements. Agenda 21 is the document resulting from this summit and it currently represents the commitment assumed by all participating nations. More than just another agreement, the Agenda 21 is a great guideline, proposing solutions and alternatives for countries capable of developing actions in favor of sustainable development .

The Agenda 21 was prepared in such a way that it can unfold at different levels: global or local, reaching community, municipal, and associative levels. Therefore, the proposals included in the Agenda are characterized by the integration of environment and development concepts, with emphasis on discussing local problems and the decentralization of decision-making. Agenda 21, as a path towards sustainability, must be understood as a development tool which works though participation and social transformation.

In this sense, social participation is a key element for development. Participation is essential during the different stages of the process, and these stages are complementary to each other. They must be part of the identification of needs, of the generation of knowledge, of the search for and implementation of solutions, and above all, of decision-making. They play an essential role in the transformation of reality.