The opening chapter of the book examines matters of theoretical debate relevant to the self-assessment approach overall. It also looks at technical points from the world of psychometrics and considers the motive for using self-assessment. Chapter 2 records the principal self-assessment devices concerning hearing impairment that have emerged to date, plus subsequent published work using one or more of these scales. Chapter 3 focuses on an analysis of data using one such scale, derived from a sufficiently varied set of backgrounds so as to allow certain methodological and epidemiological questions to be scrutinized. Chapters 4-6 address other areas of audiological and related practice and research where self-assessment has emerged.