Clinical staging of maturation in 487 white (232 male) and 239 black (166 male) youths was compared with serum gonadotropin levels. Gonadotropin patterns were similar in both male groups. Luteinizing hormone (LH) rose progressively with maturation. It is uncertain if LH plateaus in pubertal males. Mean follicle stimulating hormone (FSH) titers plateaued by mid to late puberty in both races. In both female groups mean LH concentrations reached a plateau by midpuberty. No female (more than 65 were menstruating) had LH titers in the range found during midcycle surges of adult women. FSH average titers in the white females rose until midpuberty and subsequently plateaued at lower concentrations. In contrast, in the black females there were no statistical differences between mean FSH titers at all pubertal stages. Pubertal black females seemed to have higher FSH titers during maturation than did pubertal white females. There was considerable overlap of ranges of both gonadotropins, in both races, in both sexes, at all stages of maturation. Except for LH in males, gonadotropins plateaued during puberty, suggesting that titers of FSH in both sexes and LH in females reach adult levels before full maturation.