A study examined the validity of home background at age 13, educational achievement, and work experience as predictors of adult capabilities. The population examined were members of the grade 6 Swedish school population who were born in 1948 on the 5th, 15th, and 25th in each month of that year (n=12,000, or 10 percent of the total). Data about these individuals' family and socioeconomic background, academic achievement, and employment and occupational status were obtained from a national data base on them that had been established in 1961 and periodically updated. In 1980, follow-up data intended to give a broad picture of the participants as young adults were collected by means of questionnaires mailed to three partly overlapping subsamples of the initial 12,000. Home background data were gathered on 2,339 persons (1,126 men and 1,213 women), 500 of whom were contacted for follow-up interviews. These data were supplemented by quantitative indices of the individuals' vocabulary and sequences of uninterrupted speech (obtained during the personal interviews) and self-reported estimated of educational and occupational level, working conditions and their influence, verbal and linguistic skills, civic competence, and practical skills (all of which were reported on the 1980 questionnaire). Sex proved to be a big factor in the respondents' linguistic expression, with men using more words, more different words, and more long words. Educational level was also significant, with persons having a postsecondary education using almost twice as many long words as those with a lower educational level. Findings indicate that home background influences general ability level in grade 6, verbal specificity, and plans, but does not directly influence adult educational level. Ten tables and seven figures display and illustrate the data. (MN)