Social-emotional communication difficulties lie at the core of autism spectrum disorders, making interpersonal interactions overwhelming, frustrating, and stressful. We are developing the world's first wearable affective technologies to help the growing number of individuals diagnosed with autism�approximately 1 in 150 children in the United States�learn about nonverbal communication in a natural, social context. We are also developing technologies that build on the nonverbal communication that individuals are already using to express themselves, to help families, educators, and other persons who deal with autism spectrum disorders to better understand these alternative means of nonverbal communication.