Interpersonal relationships connect household groups and communities into the social interaction networks that characterize all human societies. Interaction networks structure, and are structured by, relationships created and maintained through time, which may serve a variety of social, economic, and political purposes for those who engage in them. These relationships are important aspects of social organization that must be distilled from the archaeological record when written accounts are unavailable. Such is the case with the Middle Preclassic (c. 900 – 350 B.C.) in the Maya Lowlands, which was pivotal in the development of complex society in the region. Its temporal position between the earliest permanent settlements and the Late Preclassic, when clear evidence for hereditary inequality became widespread, makes the relationships and structures that characterized Middle Preclassic society critical targets for understanding the origins of Maya social complexity. This dissertation explores Middle Preclassic Maya social organization and development through the lenses of materials exchange and consumption, which are used to analyze participation in socioeconomic networks by different social groups. It synthesizes data from six seasons of excavation at Cahal Pech, Belize, where previous research revealed substantial Middle Preclassic occupation and suggested the early development of social ranking. I present analyses of architectural investment and depositional patterns across multiple artifact categories that suggest prevalent models of Middle Preclassic social organization do not adequately explain variability in the data, and I develop a new framework to interpret social relationships in terms of network structures. The network model combines sociological research on small-world networks with anthropological conceptions of household and community interactions. It can be employed to analyze interactions at the local, regional, and interregional scales and is grounded in an understanding of material sources and how goods move across the landscape. Socioeconomic networks are defined by linking the depositional contexts of artifacts with known source areas, and networks can be compared among different groups to discern differences in internal and external exchange connections. My research suggests that dynamic interactions within small-world networks created increasingly complex social relationships throughout the Middle Preclassic, which likely influenced the development of institutionalized hierarchy and later Maya civilization. / 1 / Sherman W Horn III