Heat grill. In small saucepan, combine barbecue sauce and apple juice concentrate; blend well. Set aside.
When ready to grill, place chicken, skin side down, on gas grill over medium heat or on charcoal grill 4 to 6 inches from medium coals. Cook 25 to 35 minutes or until chicken is fork-tender and juices run clear, turning often and brushing frequently with sauce during last 15 minutes of cooking time. Bring any remaining sauce to a boil; serve with chicken.