Amid growing controversy about the oft-cited "30-million-word gap," this investigation uses language data from five American communities across the socioeconomic spectrum to test, for the first time, Hart and Risley's (1995) claim that poor children hear 30 million fewer words than their middle-class counterparts during the early years of life. The five studies combined ethnographic fieldwork with longitudinal home observations of 42 children (18-48 months) interacting with family members in everyday life contexts. Results do not support Hart and Risley's claim, reveal substantial variation in vocabulary environments within each socioeconomic stratum, and suggest that definitions of verbal environments that exclude multiple caregivers and bystander talk disproportionately underestimate the number of words to which low-income children are exposed.