This study examined, within a multiple baseline design, the development of generalized imitative repertoires and the occurrence of contingency testing in children with autism. Generalized imitation refers to an imitative response class maintained by a conditioned reinforcer: similarity. In the case of imitation, a response class is established by reinforcement of sufficient exemplars of different imitations; the results is a general repertoire of imitating novel responses on their first presentation. Generalized imitation was facilitated through reinforcement procedures involving shaping and fading. Multiple experimenters and multiple settings have been involved to promote the generalization of imitation. Contingency testing, which has been noticed to naturally occur in typically developing children when imitated, was targeted in the examined treatment, by employing a procedure where the experimenter imitated the child. It was hypothesized that the imitation training leads to generalized imitation and that the imitation of the child by the therapist leads to the occurrence of contingency testing. The results of the study show that the shaping and reinforcement procedures determined an increase in participants' trained imitative responding but no corresponding increase in novel, probed imitative responses. The data indicate the emergence of an imitative repertoire in need of further training. Additionally, the results suggest that generalization of skills across therapists and settings has occurred. Imitation of the child by the therapist had been employed for a very small number of sessions. Notwithstanding, the results yielded an increase in the contingency testing behaviors for both participants.