Enacted in 1982, JTPA is the largest federal employment training program, with titles II-A and II-C intended to prepare economically disadvantaged adults and youths, respectively, for entry into the labor force. JTPA emphasizes state and local government responsibility for administering federally funded job training programs. In fiscal year 1995, JTPA title II-A and II-C programs received approximately $1.6 billion in funding. JTPA training programs annually provide employment training for specific occupations and services, such as job search assistance and remedial education, to roughly one million economically disadvantaged individuals. Training is provided in local service delivery areas (SDA) through service providers, such as vocational-technical high schools, community colleges, proprietary schools, and community-based organizations. The program objectives are to increase earnings and employment and to reduce welfare dependence for participants of all ages. During the NJS, participation in JTPA involved roughly 3 to 4 months of training at an average cost of about $2,400 per participant. In 1986, Labor commissioned the NJS to evaluate the impact of JTPA on adults and youths because previous findings on the effects of job training programs had been hampered by poor data and statistical problems. The NJS randomly assigned persons who sought JTPA services, and were eligible for them, to a treatment group or a control group. The treatment group was offered JTPA training, and the control group was not. The study was intended to ensure that the two groups would not differ systematically in any way except access to the program, so any subsequent differences in outcomes could be attributed solely to JTPA. The study included over 20,000 eligible participants who applied for JTPA services between November 1987 and September 1989 in 16 local SDAs. The study followed up on a sample of people in the treatment and control groups 18 months after assignment and then again at 30 months. The NJS showed mixed results on the impact of JTPA programs. Adult women assigned to JTPA training had significantly higher earnings than the control group of adult women after 18 and 30 months, but the treatment group of adult men, as well as of both male and female youths, did not have significantly higher earnings than its respective control groups. Participants assigned to receive JTPA training did not have significantly greater earnings than control group members 5 years after their assignment. For some of the four targeted worker categories—adult men, adult women, male youths, and female youths—treatment group earnings exceeded those of the control group in some of the intervening years, but any statistically significant effects disappeared by the fifth year. Annual earnings of adult men increased in each year following assignment for both the treatment and control groups. As shown in figure 1, in the first year after assignment, the average annual earnings of adult men in the treatment group grew from about $4,400 to about $6,900. This group’s earnings continued to rise in the subsequent years, reaching approximately $8,700 in the fifth year after assignment to receive JTPA training. The earnings of adult men in the control group, which did not receive JTPA training, also rose following assignment, but this group’s earnings were less than those of the treatment group for each of the 5 years. After 5 years, the difference between earnings of the treatment and control groups was not statistically significant. Five years after assignment, the treatment group’s earnings had exceeded those of the control group by approximately $300 to $500 annually, but only in the first 3 years were these differences statistically significant. Earnings of adult women showed a pattern similar to those of adult men, increasing in each year after assignment. Figure 2 shows that the annual earnings of adult women assigned to the treatment group increased from approximately $2,800 in the year of assignment to approximately $4,700 in the first year following assignment. This group’s earnings continued to climb, reaching approximately $6,600 in the fifth year. Earnings of adult women in the control group followed a similar pattern, but this group’s earnings were lower than those of the treatment group in each year, reaching approximately $6,200 during the fifth year. As with the earnings of adult men, 5 years after assignment the difference between the treatment and control groups’ annual earnings was not statistically significant. However, during the first 4 years after assignment, the differences between the treatment and the control groups’ earnings were statistically significant in each year, with treatment group earnings approximately $300 to $600 higher than control group earnings annually. The earnings of male youths in the control group, like those of adult men and adult women, increased in each year following assignment. Figure 3 shows that the earnings of male youths in the treatment group increased from approximately $2,900 in the year of assignment to approximately $4,600 in the first year after assignment. This group’s earnings continued to grow during the 5-year period, reaching a high of approximately $7,600 in the fifth year. The earnings of male youths in the control group also rose during the 5-year period following assignment, climbing from approximately $4,800 in the first year to approximately $6,800 in the fifth year. We found no significant difference between the treatment and control groups’ annual earnings 5 years after assignment. Although the control group’s earnings were higher than the treatment group’s during the first 3 years following assignment, the differences, which ranged from approximately $200 to $400 each year, were not statistically significant. During the fourth and fifth years, the treatment group had higher earnings than the control group, but these differences too were not statistically significant. Earnings of female youths showed a pattern similar to that of male youths, growing in each year following assignment. Earnings of female youths in the treatment group rose from approximately $2,000 during the year of assignment to approximately $3,300 in the first year following assignment (see fig. 4). This group’s earnings continued to climb, reaching approximately $5,400 in the fifth year following assignment. The earnings of female youths in the control group also rose during the 5-year period, climbing from approximately $3,400 in the first year to a high of approximately $5,200 in the fifth year. We found no significant differences between the treatment and control groups’ annual earnings 5 years after receiving their assignments. During the first 2 years following assignment, the control group’s earnings were higher than the treatment group’s, but the differences of less than $100 annually were not statistically significant. In the fourth and fifth years following assignment, the treatment group had earnings of approximately $100 to $300 higher than the control group, but these differences also were not statistically significant. As with earnings, employment rates of those assigned to receive JTPA training were not significantly greater than employment rates of control group members 5 years after assignment. For some of the four targeted worker categories, treatment group employment rates were higher than those of the control group in some years, but any statistically significant effects disappeared by the fifth year. The employment rates of both treatment and control group adult men peaked during the calendar year of assignment and then declined in subsequent years, eventually reaching levels lower than those of the men before entering the study (see fig. 5). For example, the employment rate for adult men in the treatment group was 87 percent in the year of assignment. The percent employed declined in the following years, reaching 72 percent by the fifth year following assignment, which was lower than the group’s employment rate of 79 percent in the year before entering the study. The adult men in the control group showed a similar pattern—their employment rate was 87 percent in the year of assignment but dropped to 71 percent in the fifth year after assignment. After 5 years, the difference between the treatment and control groups’ employment rates was not statistically significant. The treatment group’s employment rates were higher than the control group’s in each year following assignment, although the differences in the employment rates were statistically significant only in the fourth year following assignment. The pattern of employment rates of adult women was somewhat similar to that of adult men. The employment rates of adult women were highest during the calendar year following assignment, with 80 percent of the treatment group and 77 percent of the control group employed (see fig. 6). After the first year, however, the employment rates for both the treatment and control groups fell, reaching 69 percent and 67 percent, respectively, in the fifth year following assignment. These rates in the fifth year were also lower than each group’s employment rate in the year before assignment. We found no significant differences between the treatment and control groups’ employment rates 5 years after assignment. The treatment group’s employment rates exceeded the control group’s in all 5 years following assignment, usually by about 2 to 3 percent, but only in the first 3 years were these differences statistically significant. The pattern of employment rates of male youths was somewhat similar to that of adult men and women: the male youths’ employment rates peaked during the calendar year following assignment—reaching nearly 91 percent for the treatment group and over 92 percent for the control group—but then declined (see fig. 7). However, in contrast to the employment rates of adults, those of male youths were slightly higher 5 years after assignment than before assignment, reaching 81 percent for the treatment group in the fifth year, compared with 80 percent in the year before assignment. We found no significant differences between the treatment and control groups’ employment rates 5 years after assignment. While the employment rates for the control group actually exceeded those for the treatment group in the year of assignment and the first and third years following assignment, none of the differences were statistically significant. The employment rates of female youths in both the treatment and control groups peaked during the calendar year of assignment, declined somewhat over the next 4 years, and then slightly increased in the fifth year (see fig. 8). As with those of male youths, the employment rates of female youths were slightly higher 5 years after assignment than before assignment.