My research program centers on language creation, and how core properties of language that emerge during language creation shed light on the architecture of the mind. I characterize the language-like properties of the gesture communication systems (homesigns) invented by deaf children, adolescents, and adults who do not have access to conventional language input. Such studies reveal children’s contribution to language learning, and thereby enhance our understanding of typical language acquisition. My hybrid approach combines psycholinguistic methodology with an important fieldwork component in Nicaragua, in which I bring the laboratory to the participants. By studying language creation at the individual and community levels, I hope to uncover core properties of language, characterize the conventionalization of homesign systems that led to the emergence of Nicaraguan Sign Language, and identify the cognitive consequences of a lack of linguistic input.