The current study evaluated a procedure used to teach two children with autism to ask "why" questions maintained by causal information about an event. To increase the value of information as a reinforcer, the experimenter denied access to preferred items and did not provide a reason for the denial. Participants were taught to ask "why" questions and were provided with information that led them to access preferred items. To ensure that "why" questions only occurred when the information was valuable, we included a condition wherein access to preferred items was restricted but causal information was available. Both participants learned to ask "why" questions when causal information was not available and refrained from asking "why" questions when causal information was available.