We assessed the use of a microswitch‐based program for promoting ambulation responses by two children with multiple disabilities. The goals of the study were to: (a) evaluate the importance of the contingency between the target behavior (forward step) and the programmed consequence (preferred stimuli), (b) measure effects of the intervention on indices of happiness, and (c) assess the social validation of the procedure using 20 physiotherapists as external raters. The intervention involved the automatic delivery of preferred stimuli contingent on forward steps. Results showed that both participants improved their performance (forward steps and indices of happiness) during contingent reinforcement phases compared to baseline and noncontingent reinforcement phases. Moreover, physiotherapists rated the intervention as socially valid.