Technological and organisational innovation Firms' learning behavior Institutional frameworks fsQCA SUR model a b s t r a c tThe innovation systems approach, which has taken a prominent position in the academic literature, has also influenced policy-makers around the globe. Most research analyses innovation systems taking a national, regional or sectoral perspective, following a 'technological imperative'. Yet changes in institutional conditions and the importance of non-technological innovation question the accuracy and the relevance of the existing boundaries of innovation systems. These developments ask for a better understanding of how innovation systems integrate within and across different levels. Drawing on a novel combination of configurational and econometric analysis, we analyse 384 Swiss firms and identify five co-existing innovation systems: two generic innovation systems, the autarkic and the knowledgeinternalisation; one regional innovation system, the protected hierarchy; and two sectoral innovation systems, the public sciences and the organised learning. The generic innovation systems entail the 'Science, Technology and Innovation' (STI) and the 'Doing, Interacting and Using' (DUI) learning modes. These systems are structurally distinct and do not integrate. In contrast, all regional and sectoral innovation systems integrate the learning modes of the generic innovation systems and complement them with idiosyncratic elements. The perspective on co-existing innovation systems that we develop here indicates the existence of two layers of innovation systems: a 'central' layer that hosts generic innovation systems and that constitutes the foundation for a second 'surface' layer that hosts regional and sectoral innovation systems. We discuss the implications of layers of co-existing innovation systems for policy-makers and future research.