In this study the effects of lead on behavioral development of hatchling slider turtles (Trachemys scripta) from the Savannah River Site, near Aiken, SC, were examined. It was of interest to determine whether dose or size affects survival, growth, or behavior. Hatchlings from 1995 showed no significant differences in growth, survival, or behavior between control and lead-injected animals at a dose of 0.05 and 0.1 mg/g (n = 10 per group). In 1996, 48 hatchlings were divided into four groups injected with 0 (control), 0.25, 1, or 2.5 mg/g lead. Few significant differences occurred in growth or size as a function of lead treatment at 4 mo of age, but survival declined markedly as a function of lead dose. Righting response was significantly impaired by lead; time to right was directly related to lead dose. Size also affected behavior; larger hatchlings turned over more quickly and reached cover sooner than did smaller hatchlings.