Mean serum concentration dehydroepiandrosterone (DHA), DHA sulfate (DHAS), progesterone (P), 17-hydroxyprogesterone (17-OH-P), estrone (E1), estradiol (E2), and androstenedione (A) were compared from 43 boys followed longitudinally for as long as 4 yr during puberty. These data were also compared with serum levels of LH, FSH, and testosterone. Elevation is recognized early in puberty for DHAS, late in puberty for P and A, and gradually throughout puberty for E1, 17-OH-P, and DHA. When compared by age, the same general pattern is apparent with adult levels of E1 reached at age 12, DHAS and E2 by 13, and DHA, P, 17-OH-P, and A not until after age 15. Significant elevations of DHA occurred with the onset of pubic hair and voice change; elevations of DHAS occurred with the onset of genital and axillary hair growth; and testosterone increased with the onset of genital and pubic hair growth and voice change.