 Participation is the cornerstone of socially just social development and poverty reduction, and it has remained central to IID's work for four decades. During the Green Revolution of the 1970s, it became clear that boosts to agricultural production were not benefiting many of the world's poorest rural communities that depend on agriculture for their livelihoods. Enabling these communities to participate in planning and implementing their own development became a new priority. In 1985, pioneers and practitioners across the world came together at a workshop in Thailand to further explore participatory development and design a range of tools and tactics for implementing it. International community of practice was born. Students and expertise in this new field was evolving quickly. In order to document and share it, IID and the Institute for Development Studies conceived and created a new journal for practitioners. Originally called RRA Notes, the journal was renamed PLA Notes and later again as Participatory Learning and Action. Over its 25-year publishing history, it provided a voice from the field and a place for practitioners to share their experiences on the ground. With a readership of over 20,000 people in 121 countries and its International Expert Peer Review Panel, Participatory Learning and Action became a leading authority on participatory processes, addressing new and diverse challenges such as adaptation to climate change, Web 2.0 technology and youth and governance in Africa. The PLA archive on the IID website offers a substantial resource for those working to enhance the participation of ordinary people in local, regional, national and international decision-making. These pages contain the content of the journal series from 1988 to 2013, with individual articles and complete issues available for free download.