This paper contains the results of a research activity carried out within an Enterprise context, aiming at the formally definition of the Enterprise 2.0 paradigm adoption process to be applied both in public and in private organizations. Our research starts from the consideration that the demand for freedom (“freeform”) which is on the base of web 2.0 and represents one of its main success key, should not lead the organizations management willing to adopt Enterprise 2.0 principles to disregard the planning phase which is preliminary to any technological initiative. In addition, since the Enterprise 2.0 adoption involves a deep change in corporate culture, it may not relate to the same organizational models applied to traditional IT projects. The analysis of the current studies on the path to Enterprise 2.0 shows that approaches have been defined following each one a different perspective of analysis. That approaches consists in a set of guidelines and are not strictly defined from stakeholders, activities and outcomes points of view. Moving from these considerations we formally defined a process flow for the adoption of Enterprise 2.0 within an organization based on goal oriented analysis and participatory design principles. In this paper we present this process flow and discuss about the advantages of the proposed approach.