This paper first reviews briefly the literature on the acoustics of infant cry sounds and then presents two empirical studies on the perception of cry and noncry sounds in their social-communicative context. Acoustic analysis of cry sounds has undergone dramatic changes in the last 35 years, including the introduction of more than a hundred different acoustic measures. The study of cry acoustics, however, remains largely focused on neonates who have various medical problems or are at risk for developmental delays. Relatively little is known about how cry sounds and cry perception change developmentally, or about how they compare with noncry sounds. The data presented here support the notion that both auditory and visual information are important in caregivers' interpretations of infant sounds in naturalistic contexts. When only auditory information is available (Study 11, cry sounds become generally more recognizable from 3 to 12 months of age; perception of noncry sounds, however, generally does not change over age When auditory and visual information contradict each other (Study Z), adults tend to perform at chance levels, with a few interesting exceptions. It is suggested that broadening studies of acoustic analysis and perception to include both cry and noncry sounds should increase our understanding of the development of communication in infancy. Finally, we suggest that examining the cry in its developmental context holds great possibility for delineating the factors that underlie adults' responses to crying.