The Architecture of Informal Product Markets: Design, Organisation, and Innovation in Nigerian Open Markets

Nigerian open markets constitute complex socioeconomic ecosystems in which product design, spatial organisation, social networks, and informal governance systems intersect to produce adaptive and innovative commercial environments. This doctoral research theorises the architecture of informal product markets in Nigeria through an extended multi-site ethnographic investigation of product design dynamics, spatial design evolution, and innovation diffusion across four major market complexes in Lagos, Kano, Onitsha, and Aba. Informed by complexity theory, economic anthropology, and design ecology frameworks, the study applies a combination of spatial mapping, longitudinal trader interviews, product lifecycle tracing, and innovation network analysis to generate a theoretically rich account of how design knowledge is produced, shared, and applied within the informal market ecosystem. Three original theoretical contributions emerge from the analysis. First, the Market Design Ecology model reconceptualises informal markets as adaptive design systems rather than design-deficient contexts. Second, the Peer Innovation Diffusion theory explains how product design improvements propagate through trader social networks without formal intellectual property mechanisms. Third, the Spatial Design Negotiation framework accounts for how market spatial configurations emerge through collective micro-decisions rather than top-down planning. Each theoretical construct is elaborated through rich empirical illustration and subjected to structural critique against existing design and market theory. Implications extend to urban planning policy, informal economy support, and design theory in emerging economy contexts. Keywords: informal markets, design ecology, market innovation, Nigeria, complexity theory.