When febrile children attending the Walter Reed General Hospital Pediatric Clinic had their temperatures measured in an environmental temperature of 70° to 82° Fahrenheit, 50 boys and girls required an optimum placement time of seven minutes for oral temperature measurements, and 40 children required four minutes for accurate measurements of rectal temperatures. Although girls and boys reached optimum oral temperatures in a relatively similar time span, girls required a longer time to reach their optimum rectal temperatures than boys.