This paper provides a critical review of the literature on territorial innovation models (industrial districts, milieux innovateurs, new industrial spaces, local production systems, etc.). The review is organized in two stages. First, the main features of each of these models and their views of innovation are compared. Second, their theoretical building blocks are reconstructed and evaluated from the point of view of conceptual clarity and analytical coherence. It is found that despite some semantic unity among the concepts used (economies of agglomeration, endogenous development, systems of innovation, evolution, and learning, network organization, and governance), territorial innovation models (TIMs) suffer from conceptual ambiguity. The latter is mainly a consequence of the way territorial innovation is theorized, i.e. in terms of technologically driven innovation and a business culture that is mainly instrumental to the capitalist market logic. This pressing ideological priority pushes the ‘conceptual flexibility’ of TIMs across the border of coherent theory building.