Theories of early development have emphasized the power of caregivers as active agents in infant socialization and learning. However, there is variability, across communities, in the tendency of caregivers to engage with their infants directly. This raises the possibility that infants and children in some communities spend more time engaged in solitary activities than in dyadic or triadic interactions. Here, we focus on one such community (indigenous Wichi living in Argentina's Chaco Forest) to test this possibility. We examine naturally occurring attentional activity involving the mother and child among the Wichi and among Eurodescendant Spanish-speaking families living in Argentina. We engaged 16 families-8 Wichi and 8 Eurodescendant-in an observational study of interactions between caregivers and their 1- to 2-year-olds. A mixed-analytic approach revealed no differences between communities in the proportion of time infants spent alone, or in mother-child interaction. What does differ, however, is how mothers engage in these interactions: Wichi mothers spend a greater proportion of their time observing their infants than do Eurodescendant mothers. Moreover, when infants in both groups are alone, they focus their 'solitary' activities differently: Wichi infants engaged primarily in observation alone, whereas Eurodescendant infants were more focused on the object. Finally, all mother-child pairs engaged in dyadic and triadic (object-infant-caregiver) patterns of attention, but the triadic patterns differed considerably between cultures: Among Wichi, mothers actively "watched" infants as they engaged with objects, whereas Eurodescendant mothers actively engaged with their infants in joint attentional episodes. This work illustrates how attention and socialization, key mechanisms of early development, are culturally organized. A video abstract of this article can be viewed at https://www.youtube.com/watch?v=SwsOCLXubKQ. RESEARCH HIGHLIGHTS: Longitudinal, observational investigation of mother-infant interaction in two distinct Argentine cultural groups (Wichi and Eurodescendants) reveals both commonalities and clear community-based differences in interactions between mothers and their 1- to 2-year-olds. Wichi mother-infant dyads engaged primarily in visual observation of one another, but their Eurodescendant counterparts tended to engage in more verbal or physical interaction. We identify a new form of triadic interaction-lateral joint attention-among the Wichi dyads. This work underscores that attention and socialization, key mechanisms of early development, are culturally organized.