In the framework of the KM3NeT Preparatory Phase project the strategic, legal and financial issues are addressed related to the construction of an European deep-sea infrastructure housing a cubic kilometre size Cherenkov neutrino telescope and providing access for deep-sea research. Many technical issues are already addressed in the KM3NeT Design Study, started in 2006, that at the end of its work will deliver a Technical Design Report for the KM3NeT Cherenkov neutrino telescope. KM3NeT has been included in the ESFRI European Roadmap for Research Infrastructures. The Preparatory Phase will provide the grounds to bring the project to its construction stage. The Consortium performing the Preparatory Phase will include the participants involved in the KM3NeT DS. The major stakeholders are present. The work performed in the Preparatory Phase will be structured in work packages aimed at addressing the following issues: political convergence towards a pan European facility; legal, governance and financial engineering; strategic issues and international networking; integration with regional and global marine and environmental systems (i.e. EMSO); preparing the production of the telescope components and the assembly and test of the system; definition of the data handling and dissemination scheme, and the operation of KM3NeT.