Oisín has been the chief executive of Friends of the Earth since 2005. He co-founded the Stop Climate Chaos Coalition in 2007 and the Environmental Pillar of social partnership in 2009, and led the 14-year campaign for a climate law which culminated in the passing of the Climate Action Act 2021. He leads Friends of the Earth’s work to ensure that the legal framework is translated into the transformative action required to eliminate Ireland’s polluting emissions. He sits on the Board of the Irish Environmental Network, and the steering committees of Stop Climate Chaos, the Environmental Pillar. Before joining Friends of the Earth, Oisín worked for 10 years in the areas of overseas aid and human rights. He was the founding coordinator of the Latin America Solidarity Centre in 1996, moved to Belize as a community organiser among immigrant banana workers and went on to become the Fresh Fruit Manager for Fairtrade Labelling Organizations International in Bonn. Oisín returned to Ireland in 2002 to become head of policy for Christian Aid, working on trade justice, aid policy and Israel/Palestine. Oisín’s primary degree was Sociology and Political Science in Trinity College Dublin and he has a Masters in International Relations from Dublin City University.