Aaron Mair is a leader in the environmental justice movement and was elected as the 57th president and first African-American president of the Sierra Club from 2015-2017. Mair was born on November 27, 1960, and grew up in Peekskill, New York. In 1984, Mair earned a Bachelor of Arts in History and Sociology from the State University of New York at Binghamton University, which included studying at The American University in Cairo, Egypt. Mair trained at Rhode Island's Naval Education and Training Center, and in 1988, he departed from SUNY Binghamton's Political Science Doctoral Program to work for the New York State Department of Health in Albany, where he is currently an epidemiological-spatial analyst. In 1998, after a decade-long campaign that closed the toxic ANSWERS (Albany New York Solid Waste to Energy Recovery System) solid waste incinerator, Mair won a $1.4 million federal Resource Conservation and Recovery Act settlement with New York State, which he used to create two nonprofit environmental justice and community service organizations. After joining the Sierra Club in 1999, Mair held leadership positions at every level: in the Hudson Mohawk Group of the Atlantic Chapter; as chapter chair of the Atlantic Chapter; as chair of the National Diversity Council and of National Environmental Justice and Community Partnerships; as an elected member to the national Sierra Club board of directors in 2014 and in 2019; and as president of the Sierra Club from 2015-2017. Mair has four daughters, three with his first wife, and one with his current wife. In this oral history, Mair discusses his genealogical research into his family's ancestry; his childhood along the Hudson River; his education; his career with the New York State Department of Health, including as a 9/11 emergency responder; his three-decades of work in the environmental justice movement; and his two-decades of leadership in the Sierra Club, particularly on issues of equity, inclusion, and justice.