Crying behavior and mother-infant interactions during episodes of crying were coded using the Cry Observation Codes and then compared for 48 mother-infant dyads of children with autism, children with developmental delays, and typically developing children. At 1 year of age, children who would later be diagnosed with autism showed a different pattern of cry compared to the children in the comparison groups; specifically, their cries had less waveform modulation and more dysphonation. Maternal reactions to the crying of infants later diagnosed with autism were qualitatively different from the responses to cries of the other children of the same age (fewer tactile or vestibular stimulation and more verbal production). Implications of the study are described. (Contains 3 tables.)