This book provides a theoretical lens through which to view Disability. Rather than taking a medical-diagnostic stance, which has been the traditional perspective, the authors explain disability as category in which membership is based on of judgments about explanations for what people do, experience and how they appear. In Part I, the authors discuss various aspects of the history and current trends, which influence how disability is defined and addressed. In Part II, Explanatory Legitimacy' (EL) theory is explained in detail and applied to an analysis of disability. In Part III, the EL theory is applied to rethinking disability now and in the future.