In a quantitative observation study, we unobtrusively examined purchase-related communication between 0- to 12-year-old children and their parents (N = 269 dyads) during supermarket and toy store visits. The aims of the study were to determine (a) the development of purchase-related parent-child communication (i.e., children's purchase influence attempts, their coercive behavior, parent-initiated communication) and (b) the relative influence of different socialization variables (e.g., television viewing, family communication patterns) on these communication variables. Our inverted-U hypothesis for the effect of developmental level on purchase influence attempts received support: Children's purchase influence attempts increased until early elementary school and started to decline in late elementary school. Our inverted-U hypothesis for the effect of developmental level on coercive behavior was also supported: Children's coercive behavior was highest among preschoolers. With increasing age, children were more likely to be involved in the purchase decision-making process, and parent-child communication more often resulted in a product purchase. Finally, children's television viewing was the most important (positive) predictor of their purchase influence attempts.