Purpose – The open data movement is a a global trend for the opening of governmental data and the delivery of these data onto connected internet servers. The main argument for open data is that it will enhance the governmental transparency, and will promote the creation of new services for citizens by third parts. Despite its global success, open data initiatives utilizability for end users is often questionable and limits its social impact. This paper relates the case of an open data initiative designed around a user centered methodology, and proposes operational recommendations for further open data projects. Design/methodology/approach – During the U-Home project we used a participative design methodology, that could be described as opened or participative (Chesbrough, vanhaverbeke, West, 2006), more horizontal (Von Hippel, 2005) or even an ascending process (Cardon, 2005). The aim of this method is to imply all the stakeholders (users, partners, developers, etc.) during the innovation project to maximize the social utility and acceptability of the result. Originality/value –This methodology is an alternative to most of the former open data initiatives, consisting in creating open data portals, and inciting independent innovators to developp third services. In this classical case, the Open Data initiative relies onto the energy and the power of entrepreneurs/developers, willing to create business from a newly appeared resource (Data). Practical implications – Our work proposes to public agencies to play a new role in open data initiatives. They are not only data providers, but also partners that can facilitate and cooperate with data projects. Our work also insiste on the role of human sciences to imply end users at every stage of the project.