The issue unresolved: innovating and adapting disability programs for the third era of Social Security.

The history of the Social Security programs in the United States falls into several distinct eras, defined by changing social, demographic, and economic conditions. At present the retirement component of these programs is moving into a stage of program maturation, which poses certain relatively well-understood changes to policymakers. The disability programs are also moving into the same set of societal conditions, but their impact is considerably more difficult to predict. Already disability incidence rates have experienced disturbingly large and poorly understood shifts. Developing a way to predict these shifts and to deal with the challenges that they make for existing programs is therefore a major priority of Social Security's current research agenda.