The terminology and conceptual framework for describing Participatory Guarantee Systems (PGS) was first developed from the International Alternative Certification Workshop held in Brazil in 2004 and sponsored by IFOAM - Organics International and the MAELA. During this event, the dynamics of different alternative organic certification systems were shared and their common features documented, allowing for a common definition to be identified. The officially adopted definition states: “Participatory Guarantee Systems (PGS) are locally focused quality assurance systems. They certify producers based on active participation of stakeholders and are built on a foundation of trust, social networks and knowledge exchange.” (IFOAM - Organics International, 2008) Since 2004, PGS have gained recognition throughout the world, in the organic sector, and in the agroecology movement, as credible, relevant and cost-effective mechanisms through which producers can guarantee that their products have been produced according to the four principles of organic agriculture4. IFOAM – Organics International recognizes the full diversity of organic agriculture, including terms of verification or quality assurance systems. PGS are alternative and complementary to ISO-type independent third-party certification: just like third-party certification systems, PGS consist in quality assurance systems that aim to provide a credible guarantee for consumers seeking organic produce.