Does early gesture use predict later productive and receptive vocabulary in children with pre- or perinatal unilateral brain lesions (PL)? Eleven Children with PL were categorized into 2 groups based on whether their gesture at 18 months was within or below the range of typically developing (TD) children. Children with PL whose gesture was within the TD range developed a productive vocabulary at 22 and 26 months and a receptive vocabulary at 30 months that were all within the TD range. In contrast, children with PL below the TD range did not. Gesture was thus an early marker of which children with early unilateral lesions would eventually experience language delay, suggesting that gesture is a promising diagnostic tool for persistent delay.