The purpose of this study was to evaluate the effect of two AAC technologies on indices of happiness for school-age children with multiple disabilities during interactions with their school speech-language pathologists. The study applied a post host secondary analysis of a previously completed single-subject alternating treatment design study including three school-age children with multiple disabilities. The study compared two AAC technology treatment conditions, one high-tech and one low-tech. The secondary analysis revealed that the children displayed more indices of happiness when interacting in the high-tech AAC condition than the low-tech AAC condition. Nonoverlap of all pairs (NAP) calculations estimated a medium or large effect of AAC mode for the participants. This study is limited in scope and by its use of post hoc analysis, but it adds to existing evidence suggesting the benefits of high-tech AAC intervention using personalized color photos, mobile technology, and voice output for school-age children with multiple disabilities. It also shows the potential of indices of happiness to inform clinical decision making for children with multiple disabilities. Future research should continue to evaluate the comparative effects of differing technologies and instructional strategies on indices of happiness to maximize opportunities for communication and language learning.