Interrelations of adolescents' psychological functioning and endocrine and physical growth variables are investigated. Participants are 56 boys and 52 girls, 9 to 14 years old, and their parents. Participants were evaluated on biological and psychological variables at three times of measurement, six months apart. Biological measures include stage of pubertal development (Tanner stage), assessed by a physical examination, and hormone levels, assessed by serum levels of gonadotropins, gonadal steroids, adrenal androgens, and cortisol. Psychological measures include assessments of behavior problems, affective states, interpersonal functioning, parent-child interactions in standard laboratory situations, and cognitive functioning. Relations between hormone levels and anxiety and depressive symptoms, parent-child interactions, and cognitive functioning were examined. Hormone levels of boys, primarily gonadal steroids and adrenal androgens, were predictive of anxiety and depressive symptoms one year later. Hormone levels, per se, were not predictive of anxiety and depressive symptoms one year later in girls. A more rapid rate of change (across one year) in level of adrenal androgens in boys and gonadotropins in girls was accompanied by a higher incidence of anxiety and depressive symptoms at the year's end. Relations between hormone levels and the adolescent's use of anger and power in parent-adolescent interactions indicated that boys with higher levels of androstenedione were higher on explosive behavior. Girls with higher levels of androstenedione were higher on dominance, defiance, and expression of anger toward both mother and father. Relations between hormone levels and degree of peripheral target tissue exposure and cognitive functioning indicated that boys with higher testosterone levels and a greater degree of peripheral target tissue exposure were higher on spatial abilities than boys with less exposure to circulating gonadal steroids. Neither hormone levels nor degree of peripheral target tissue exposure was related to spatial abilities in girls.