When you cannot measure, your knowledge is meager and unsatisfactory."-Lord Kelvin 1 "If you are not counted, you don't count."-Cyndi Jones, Center for an Accessible Society Efforts to provide statistics on the number and status of workingage people with disabilities have a history of being fragmented and sporadic. As a group, they are often overlooked in mainstream discussions of the latest statistics on employment, income, poverty, and other measures of the status of the population. In contrast, government agencies routinely compile and report such statistics for groups defi ned by sex, age, race, ethnicity, and marital status. Indeed, one of the most frequently cited statistical reports on the socioeconomic status of the U.S. population-the U.S. Census Bureau's Annual Report on Income, 2 Stapleton, Houtenville, Weathers, and Burkhauser Poverty, and Health Insurance Coverage in the United States-does not mention this group. The overarching objective of this book is to support and facilitate efforts to improve statistics and data on working-age people with disabilities. Many of the limitations with statistics and data on this population are well-known. There have been signifi cant efforts to address the limitations, and some progress has been made. That progress, however, has often been at the whim of external forces, such as the extent of support for improvements to federal data collection, advances in information technologies, concerns about privacy protection, and government expenditure priorities, rather than for the purpose of systematically capturing the size and socioeconomic characteristics of this population. As a result, statistics and data for working-age people with disabilities are not on par with those for other "at-risk" working-age populationsgroups that are more likely than others to experience adverse socioeconomic outcomes, such as some racial and ethnic minorities, children, unmarried parents, and the elderly. This book provides a systematic review of what current statistics and data on working-age people with disabilities can and cannot tell us, and how they can be improved to better inform policymakers, advocates, administrators, analysts, service providers, and others. This book will inform two broad audiences. The fi rst consists of those interested in what current data can tell us about the prevalence of disabilities among working-age people and their socioeconomic status, but who are dissatisfi ed with the limited, and often confusing, statistics cited in the mainstream press. For this audience, the book also offers the best available statistics on levels and trends in their employment, income, poverty, and health and functional status. The second audience is a more specialized group of professionals (academics, advocates, government policymakers, service providers, etc.) who require reliable information to support evidence-based public policy and administrative decisions. For them, we go beyond "facts" to 1) examine how robust these facts are across data sets, 2) consider the strengths...