Contents lists available at ScienceDirect Cities journal homepage: www.elsevier.com/locate/cities Urban open spaces as a commons: The credibility thesis and common property in a self-governed park of Athens, Greece Paschalis A. Arvanitidis*, George Papagiannitsis Department of Economics, University of Thessaly, 78, 28th October str., 38333, Volos, Greece ARTICLE INFO Keywords: Commons Socio-Ecological Systems (SES) Credibility thesis Formal, Actual and Targeted (FAT) institutional framework Endogenous property rights ABSTRACT Although abandoned, unused or underused urban open spaces can play an important role in urban well-being, the traditional approaches of state management and privatization have failed to revive them, due to the lack of necessary public funds, low private investment interest or the vagueness of property rights. Therefore, a solution might be to manage this land as a commons, where local users collectively undertake governance of the resource. The current paper explores a successful initiative, the Navarinou Park initiative in downtown Athens, in an attempt to consolidate the experience gained and to draw policy recommendations for the success of such ac- tions. In this endeavour, the paper employs Ostrom’s Socio-Ecological Systems (SES) framework to analyse the park as a commons and then, building upon this, proceeds to explore the credibility of the institution along the lines of the credibility thesis and its underlying theory, with particular reference to the Formal, Actual and Targeted (FAT) institutional framework. The paper concludes that Navarinou Park is a functional, long-standing and credible institution, successfully serving the manifold needs (recreational, environmental, social and poli- tical) and interests of the local population. Thus, in line with the Credibility Scales and Intervention (CSI) checklist, an advisable intervention would likely comprise a subtle blend of condoning and co-opting; govern- ments to leave the daily praxis undisturbed while fostering a regime within which this praxis is permitted to flourish. 1. Introduction There is a general acknowledgement that formal private property rights are vital to sustainable development (Rodrik, 2004; World Bank, 2002). But while it might be relatively easy to officially define such property rights, there are abundant instances where credible im- plementation is far from simple. Many countries, including Greece, exhibit specific institutional and organizational deficiencies (e.g. over- lapping or ambiguous legal rights, rigid and bureaucratic judicial pro- cedures, weak policing and enforcement mechanisms, high transaction and administrative costs) which preclude successfully realizing such formal establishments (Arvanitidis & Nasioka, 2015; Arvanitidis, Nasioka, & Dimogianni, 2015; Colville, 2012; Hatzis, 2018). In turn, Greek society has resorted to various collective institutional arrangements (mainly of an informal character) enabling groups of people to effectively manage certain resources in a socially acceptable and sustainable way. In the last years, these arrangements took the form of grassroots movements and even guerrilla initiatives (such as those related to urban community gardens of a green-guerrilla type), largely in response to the harsh economic distress both Greek society and the Greek state have experienced after the 2009 government-debt crisis, the subsequent collapse of the Greek economy and the austerity measures imposed (Anthopoulou, Nikolaidou, Partalidou, & Petrou, 2017; Cappuccini, 2018; Daskalaki, 2018; Kavoulakos & Gritzas, 2016; Kioupkiolis & Karyotis, 2016; Partalidou & Anthopoulou, 2017; Stavrides, 2014; Vaiou & Kalandides, 2016). Under these conditions, public finance for the provision and maintenance of urban open spaces (UOS) 1 has been substantially curtailed, leading both to the degrada- tion of these spaces, while also providing a terrain encouraging social movements seeking to collectively undertake the appropriation, use and https://doi.org/10.1016/j.cities.2019.102480 Received 28 February 2019; Received in revised form 22 July 2019; Accepted 9 October 2019 ⁎ Corresponding author. E-mail address: parvanit@uth.gr (P.A. Arvanitidis). 1 We use ‘urban open space’ (UOS) as an over-arching term encompassing a variety of public, semi-public and private spaces within the urban frame that are generally open, freely accessible and available for use by people for recreation, amenity and socialization purposes (Arvanitidis & Nasioka, 2017). As such, UOS includes parks, playgrounds, squares, plazas, land trusts (school and church yards, vacant and unused plots, etc.), walkways and other such urban spaces. UOS is of vital importance for people’s well-being by providing aesthetic, ecological, physical, psychological and social benefits to urban residents (Arvanitidis, Lanenis, Petrakos, & Psycharis, 2009; Wolch et al, 2014). Cities 97 (2020) 102480 0264-2751/ © 2019 Elsevier Ltd. All rights reserved. T