The behavior of newborns is ambiguous. Cultural models--representations shared by members of a community--provide new parents and others with a cognitive and motivational structure to understand them. This study asks members of several cultural groups (total n = 100) to judge the "similarity" of behavioral items in the Neonatal Behavioral Assessment Scale (NBAS). Data were obtained from NBAS experts, mothers, and undergraduates in Massachusetts, and mothers and high-school students in rural Kenya. Multidimensional scaling of their judgments reveals that NBAS experts were especially attentive to a dimension of State Control--exactly as the scale emphasizes. Kenyan mothers focused on a dimension of motor responsiveness--in accord with their concern and practices regarding motor development, and the Massachusetts mothers organized their judgments around cognitive competence--abilities emphasized in contemporary discussions of early development. The US students appear to be more similar to US mothers than did the Kenya students to the Kenyan mothers. Each adult group's representation reflects their cultural values and goals, and helps them understand the newborn child in local terms.