Contains extensive information on the changing circumstances of aged and disabled beneficiaries. Based initially on a national cross-sectional survey of new beneficiaries in 1982, the original data base has been expanded with information from administrative records and a second round of interviews in 1991. Variables measured in the original New Beneficiary Survey (NBS) include demographic characteristics; employment, marital, and childbearing histories; household composition; health; income and assets; program knowledge; and information about the spouses of married respondents. The 1991 New Beneficiary Follow-up (NBF) updates marital status, household composition, and the economic profile and contains additional sections on family contacts, postretirement employment, effects of widowhood and divorce, major reasons for changes in economic status, a more extensive section on health, and information on household moves and reasons for moving. Disabled-worker beneficiaries were also asked about their efforts to return to work, experiences with rehabilitation services, and knowledge of SSA work incentive provisions. The NBDS contains unique measurements that make it valuable not only for studies about Social Security but also for studies of health, economic, labor, gerontological, and welfare issues. It contains objective measures from administrative files of yearly covered earnings from 1951 to 1992, Medicare expenditures from 1984 to 1999, whether an SSI application has ever been made and payment status at 5 points in time, and dates of death as of spring 2001. For studies of health, the Medicare expenditure variables include inpatient hospital costs, outpatient hospital costs, home health care costs, and physicians' charges. The survey data cover functional capacity including ADLs and IADLs. For studies of work in retirement, the survey includes yearly information on extent of work, characteristics of the current or last job, and reasons for working or not working. No other data set has such detailed baseline survey data of a population immediately after their retirement or disability enhanced with subsequent measures over an extended period of time.