This paper introduces a formal model of economic complexity formation based on causal factors and mechanisms of system development. I use the framework of complex adaptive systems to explore the development of socio-economic complexity in past societies. The model will be applied to a case study of two communities, Sagalassos and Duzen Tepe, in southwest Turkey during the late Achaemenid and early Hellenistic periods. It is shown how observations of material culture related to resource procurement, production processes, production output, and structures of exchange can be used as proxies to approximate the intensity of causal factors contributing to the development of socio-economic complexity at a local scale.