Job Corps is a national education and training program for at-risk youth between ages 16 and 24. Administered by the U.S. Department of Labor (DOL), the program provides vocational, academic, health, and supportive services, primarily in a residential setting at Job Corps centers. The program's objective is to help disconnected youth become more responsible, employable, and productive citizens. Between 1993 and 2004, DOL sponsored the National Job Corps Study to examine the effectiveness of the program as it operated in the mid-1990s. The impact evaluation used an experimental design, in which all eligible program applicants nationwide between late 1994 and early 1996 were randomly assigned to a program group who could enroll in Job Corps or to a control group who could not (but who could enroll in other available programs in their communities). The original evaluation examined outcomes through 2001, and a later follow-up study examined longer-term earnings impacts using tax data through 2004, roughly nine years after random assignment.

This follow-up study assesses longer-term employment-related impacts of Job Corps using tax records through 2015, about 20 years after random assignment. The 20-year follow-up study addressed the following research questions:

1. Twenty years after random assignment, what were the impacts of Job Corps on participants' annual employment and earnings overall and by age group?
2. What were impacts on types of employment (hourly wage and salaried employment, contractor employment, and self-employment); the receipt of Social Security Disability Insurance (SSDI) benefits; and spouse employment? Did the program have an effect on tax filings, liabilities, and balances due?

The 20-year results largely mimic the results from the nine-year study using the tax data. The study finds evidence that the positive program effects persisted, but did not grow, for the 20- to 24-year-olds. Furthermore, the older program group earned more, on average, than the older control group throughout the period, although their earnings gain in 2015 is not statistically significant. However, as with the nine-year study, the study finds no evidence of long-term program effects on employment and earnings overall or for the 16- to 19-year-olds in years 10 to 20. The study findings do not change previous conclusions from the benefit-cost analysis. Specifically, the longer-term results support the findings that (1) for all participants, program benefits to society were smaller than program costs; (2) the program was cost-effective for the 20- to 24-year-olds; and (3) benefits exceeded costs from the perspective of program participants.