Children learn language at incredible rates, and a plethora of research has examined the mechanisms and trajectories of young children’s language development. However, human language consists of more than words and syntax—it conveys meaning for the purpose of communicating with others. This dissertation centers on the following question: How do children learn to use language to communicate? To begin tackling this question, I consider the kinds of interactions that children engage in. First, I ask how parents play a role in scaffolding children’s communicative development by adapting the way they speak, both generally and specifically, to their children’s developmental level and knowledge (Chapters 1 and 2). I find that parents of children (ages 2-8) adjust the vocabulary as well as communicative strategies they use during cooperative games to ensure communicative success. Then, I ask how children might learn to communicate with peers, and the development of component skills required for adapting to others in conversation (Chapter 3). I find that while children as young as 4 are sensitive to what words are learned earlier or later (even when they themselves know all the words in question), they may not spontaneously adapt their language when communicating with another child. Finally, I present a theoretical framework of conversational adaptation, specifically considering how perspective-taking occurs (or fails to occur) in both adults and children. I hypothesize that in-the-moment processing demands is the key factor driving communicative success and failure in adults and children alike (Chapter 4). This dissertation seeks to understand the development of children’s communicative skill by examining the interactive contexts that children engage in, and aims to present a holistic picture of language learning—one that does not isolate the child from their environment, but one that considers the rich input that children receive through interactions that are designed for them.