Teaching an infant manual signs is beneficial as it promotes early communication, improves socialization, and can functionally replace behaviors such as crying and whining. Improving early communication also may reduce the probability of an infant engaging in dangerous behavior, like unsafe climbing. The purpose of this study was to extend Thompson et al. (Journal of Applied Behavior Analysis 40:15-23, 2007) by teaching an 8-month-old infant, who was noted to display developmental delays, to sign for "help" when preferred items were inaccessible. Similar to Thompson et al., delayed prompting and differential reinforcement was efficacious in teaching the infant to sign for "help," and the skill generalized to situations that were previously associated with unsafe climbing. However, undesirable generalization of signs for "help" when the infant could independently access the items was observed. Additional teaching was necessary to ensure signing for "help" occurred under appropriate antecedent control.