Tests for delayed cutaneous hypersensitivity were carried out with Candida and streptokinase-streptodornase antigens in 245 normal pediatric subjects, ranging in age from 17 days to 5 10/12 years. The group comprised patients with a variety of acute illnesses and a series of control subjects. There was a progressive increase in the frequency of cutaneous responses with age. About one-third of infants under one year and four-fifths of one to five-year-old children had positive induration reactions to at least one antigen. Candida was the more reactive antigen in the first year of life; thereafter there was comparable responsiveness to both antigens. Our results showed no difference in percent reactivity between acutely ill and control subjects.