Stephen Gilson is an American theorist and policy analyst who is best known for his work in disability, diversity, and health policy through the lens of legitimacy theory and disjuncture theory. Co-authored with Elizabeth DePoy, Gilson developed Explanatory Legitimacy Theory. Through that lens, Gilson analyzes how population group membership is assigned, is based on political purpose, and is met with formal responses that serve both intentionally and unintentionally to perpetuate segregation, economic status quo, and inter-group tension. Additionally, co-authored with DePoy, Gilson developed Disjuncture Theory. This theory explains disability as an interactive “ill-fit” between bodies (broadly defined) and environments (broadly defined). Gilson has applied legitimacy theory and disjuncture theory to the analysis and enactment of health policy and practices related to access and to illness prevention. Along with DePoy, Gilson has implemented his vision of socially just policy based on universal access principles through the creation of a web portal that renders existing illness prevention information accessible to individuals across diversity category boundaries. Gilson has received invitations to keynote at national and international conferences on disability studies and distinguished lectures at University of Illinois at Chicago, University of Michigan at Ann Arbor, Smith College, NYU, University of North Carolina, Ono Academic College, Research Institute for Health and Medical Professions, and others. Biography Gilson was born in 1950 in Long Beach, California, to a family of three—an older brother, Michael, and his mother and father, Janet and Arnold Gilson. Later, in 1955, a younger sister, Nancy, would join them. He spent years as an artist before earning a BA in 1973, and PhD in 1991 from the University of Nebraska Medical Center. Recent activities In Rethinking Disability, first published in 2004, and Disability as Disjuncture, currently in press, Gilson with co-author Elizabeth DePoy, takes on the essentialist nature of current diversity categories with a particular focus on disability, laying bare the value foundation and political and economic purpose of “disability category” assignment and social, professional and community response. His subsequent works, also co-authored with DePoy, include The Human Experience, published in 2007, Evaluation Practice (2008), Studying Disability (2010), and selected essays and papers. This scholarship applies legitimacy and disjuncture theories to understanding theories of human description and explanation and their purposive, political use in diverse “helping professional” worlds. Recently, Gilson, with co-author DePoy, applies design theory and practice to the analysis of diversity categories, their membership and their maintenance. In his