Archaeological investigations in northern Manabí, Ecuador have included regional settlement surveys and excavations that have identified a previously unknown Terminal Valdivia cultural complex named the “Piquigua Phase” (1700-1550 B.C.). Consequently, these archaeological investigations established the Jama River Valley as the northernmost frontier of the Valdivia society. Yet, the excavations at the site of Matapalo, in the Coaque River Valley, have pushed these frontiers further north. Thus, expanding the Valdivia occupations into new lands based on the reported archaeological features, cultural diagnostics and radiocarbon dates obtained at the site. By employing the methodology of modal analysis to the ceramic material from Matapalo, it was possible to recognize the formal and stylistic variability of the vessels, most of which reoccur in other sites with a Terminal Valdivia affiliation. Additionally, the ceramic analysis imparted in this thesis revealed that pottery is a particularly informative record of technology, chronology, but most importantly culture.