The prevalence rates of children being diagnosed with autism spectrum disorder (ASD) continue to rise at alarming rates. Recent figures suggest that approximately 1 in 90 children have an ASD. Children with ASD have significant deficits that affect communication skills and social interaction. Children with ASD may also engage in high levels of aberrant behavior toward others or themselves such as screaming, hitting, or biting that interfere with learning. The current study examined the effects of functional communication training on young children with ASD when implemented by a paraprofessional in a special education classroom. Data were collected on the rates of and communicative responses and aberrant behaviors. Generalization data were also collected. Findings indicated that when functionally relevant consequences were delivered following an appropriate communicative response, a reduction in aberrant behaviors and an increase in appropriate communicative responses were noted.