**6. Conclusions**

Institutionalized Smart City initiatives are aimed at delivering better structural advantages to cities [1]. It is argued that, in the context of an increasingly competitive globalized world, the Smart City model in its mainstream formulation can deliver a better city governance, taking advantage of the ICT possibilities developed by means of public-private partnerships [51,52]. In national contexts such as our case study, in Spain, institutionalized networks are expected to be particularly beneficial to medium-sized cities and firms. However, from a more critical perspective, it could be argued that the expansion of the Smart City paradigm in national arenas can become a gateway for bigger firms to expand their market possibilities, without changing the hierarchy of cities, if not reinforcing existing inequalities [53–55].

This paper has explored the relations of centrality and hierarchy between cities and firms implementing Smart City strategies in the context of the Spanish Network of Smart Cities (RECI) as of 2018. Since the literature has usually focused on the global dimension of cities and firms networks [15], exploring a national case offers interesting insights about the presence of multinational firms in these contexts and the role played by medium-sized cities in their market expansion. Building on a two-mode network of cities and firms participating in Smart City projects, we have explored whether the structural advantages from participating in these networks have a leveling effect or rather reinforce existing hierarchies of cities. We have also analyzed how national and multinational corporations are interrelated in Smart City projects and whether medium-sized local companies have a relevant presence or not. Our findings suggest that these networks become a regional gateway for multinational firms to expand their presence in Smart City national markets, rather than empowering medium-sized cities and small national firms. Thus, our results suggest that an institutionalized network in a national context can indeed reflect the existing hierarchy of cities, while acting as a gateway for foreign multinational companies to have an emerging access to a growing market, rather than providing better structural advantages to medium-sized cities and local companies.

These elements should be taken into consideration when designing and implementing institutionalized policies on Smart cities, taking into account that national Smart City policies (with specific objectives such as promoting Smart City industry clusters) may not be fully aligned with local Smart City strategies (centered on implementing the best solutions available). While it might be difficult to reconcile the multiple rationalities behind the promotion of Smart City initiatives, instruments such as networks of cities may help to reconcile both perspectives, if their functioning is carefully analyzed and there is the clear objective of preserving public interests over private ones.

**Supplementary Materials:** The following are available online at http://www.mdpi.com/2071-1050/12/12/5219/s1, Table S1, Corporations identified as participating in smart city projects in cities member of the RECI by the number of cities in which they are involved; Table S2, RECI city members by the number of corporations identified as participating in smart cities initiatives that were present in at least 2 cities of the network; Table S3, Pairs of cities that shared at least three corporations involved in smart city projects; Table S4, Pairs of corporations that shared participation in three or more cities; Table S5, Centrality and hierarchy in the RECI corporate networks; Table S6, Centrality and hierarchy in the RECI city network.

**Author Contributions:** Conceptualization, I.S., R.R.-F., H.M. and L.C.-M.; methodology; I.S. and L.C.-M.; formal analysis; I.S. and L.C.-M.; investigation, I.S.; data curation, I.D., I.S. and L.C.-M.; writing-original draft preparation, I.S.; writing-review and editing; I.S., R.R.-F., H.M. and L.C.-M.; visualization, I.S. All authors have read and agreed to the published version of the manuscript.

**Funding:** The authors wants to express their gratitude for the internal funding of the Internet Interdisciplinary Institute (IN3)-Universitat Oberta de Catalunya (UOC) that contributed to develop this project.
