More than 2 million adults participate in programs provided by elementary and secondary schools, almost 8.5 million adults receive training from postsecondary schools, nearly 4.5 million participate in private employer-provided programs, and government agencies account for almost 4.5 million adult participants. Demographic data suggest that young, white, well-educated, higher-income, higher-occupational-status, employed adults have the highest participation rates. Reasons for nonparticipation are related to socioeconomic status, race, and prior educational attainments. Examination of training programs that have been successful in removing many of the barriers to participation in training, especially for adults in a career transition, indicate that successful programs are likely to involve collaboration or partnership among business, education, organized labor, and community agencies; offer flexible curricula and scheduling; offer supportive services; combine modes of instruction; offer remedial instruction; encourage peer support groups; gear programs to the wants and needs of those being served; and provide training for emerging, high-demand jobs or careers. A single, longitudinal database is needed to provide information on patterns, reasons for, and barriers to participation in education and training. Also needed are alternative methods of data collection to improve assessment of the sociopsychological, situational, and structural barriers to participation in adult education and a research agenda providing for hard evaluation of program outcomes. (MN)