This chapter explores socio-economic ecosystems as processes of complexification. A conceptual model is introduced where isomorphic structures of complexity grow within nested hierarchies, progressing from individuals to practices and routines, organizations, and market systems. Rather than viewing these systems through a reductionist lens—as static entities or aggregates of resources—this analysis emphasizes how structures emerge through relational dynamics and interdependencies. Drawing on complex adaptive systems theory, we propose a framework based on a relational ontology of process that offers a systemic-evolutionary perspective on how socio-economic systems emerge and adapt. The study positions complexity theory as a versatile framework applicable across disciplines. Its systemic-evolutionary approach provides a unifying lens for fields such as management, organizational theory, and service theory, facilitating an integrated perspective that spans traditional disciplinary boundaries. Such transdisciplinarity resonates with a growing body of work advocating for frameworks that can address the complex, interconnected, and dynamic nature of modern socio-economic phenomena.