Negotiations are critical to interpersonal interactions, yet little is known about how the conceptual skills that support successful negotiations develop in childhood and across societies. Here, we presented 384 3-10-year-old children in the United States and India with tasks that measured children's understanding that people can value the same resources differently (Experiments 1-4) and that underlying interests motivate people's stated positions (Experiment 5). In Experiments 1 and 2, children participated in a third-person resource distribution task. Children distributed resources (candies) to two targets who valued resources differently: absolute preferences (liking A but disliking B) or relative preferences (liking both but preferring A to B). By age 5, children differentiated relative from absolute preferences. Experiments 3 and 4 presented a first-person variant of the same task. In trials involving a conflict in which both the child and the target preferred the same resource, U.S. children prioritized their own preferences, whereas Indian children prioritized the targets' preferences. In Experiment 5, all participants from the previous studies participated in an additional task in which two people wanted a single resource, an orange, but their interests differed-one wanted the pulp to make juice and one wanted the peel to make cake. With age, children increasingly proposed the value-maximizing option of splitting the peel from the pulp, rather than halving the orange. Notably, even the youngest Indian children chose the value-maximizing option. Our findings outline the development of two antecedents to successful negotiations and highlight the disparate role of self-interest across cultural contexts. (PsycInfo Database Record (c) 2022 APA, all rights reserved).