1 This is the Accepted Author Manuscript; the published final article can be found at: Konstantinou Z.I., Kombiadou K. & Krestenitis Y.N., 2015, Effective mussel‐farming governance in Greece: Testing the guidelines through models, to evaluate sustainable management alternatives, Ocean & Coastal Management, 118 (B), 247–258, http://dx.doi.org/10.1016/j.ocecoaman.2015.05.011 Effective mussel‐farming governance in Greece: Testing the guidelines through models, to evaluate sustainable management alternatives Zoi I. Konstantinou*, Katerina Kombiadou, Yannis N. Krestenitis Department of Civil Engineering, School of Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece * Corresponding author .E‐mail address: zkon@civil.auth.gr Abstract The last twenty five years multiple management issues concerning the suspended farming of filter feeding bivalves in Greece have emerged from the deficient implementation of different legislation regimes, that, on their own account, have been proven insufficient. Specifically, regarding the planning and management of cultivation areas, multiple alternatives have been proposed through the years, with some still being under consideration. Yet most of them were selected based on purely spatial criteria and none has been thoroughly investigated, regarding the system's carrying capacity. As the current governance structure, in combination with the previous and current legal framework, seems unable to solve the existing problems, a question arises: are the “legal” solutions the optimum –or even among the best‐ regarding the environmental and socio‐economic sustainability of the coastal aquaculture in the areas under consideration? In this paper we attempt a discussion between science and management, regarding the 3 main mussel‐farming areas of Thermaikos gulf, Greece: Chalastra, Imathia and Pieria. The tools that were designed in the context of integration between science and policy are used in order to investigate the appropriate structure and flexibility of the legal framework controlling the activity and the governance level in which this control should take place. Previous and ongoing research results from combined management models, implemented or developed, for the mussel‐farming areas of Thermaikos gulf are the starting point of this discussion. The goal is to detect “weak spots” of the current legal framework and to investigate if and how scientific management tools can assist in the development of more flexible, yet more effective environmental legislation. Keywords: governance, mussel farming, spatial planning, management tools 1. Introduction When discussing the term “integrated management” of coastal and marine activities, it is anticipated that, at some point, the discussion will have to involve: (a) the level of governance in which essential management decisions are taken and (b) the governance tools used to implement these decisions, i.e. the various forms of legal instruments. These instruments may vary significantly both in power