The Preliminary Design Process (PDP) has a great impact on the product development process. However, there is a lack of Computer Supported Cooperative Work in Design (CSCWD) systems and associated methods to support and improve the work of the design team members during PDP. In this paper after a literature review of PDP methods, we identify the key elements that should be taken into account to improve the PDP through the use of a CSCWD system. We expose our hypothesis: the use of a CSCWD system, supported by a proper PDP model and a specific ontology, can augment the collaboration and the creativity (number and quality of concepts generated) of the design teams and so improve the performances of the PDP itself. We then present our research project and explain why design methods and CSCWD system should evolve jointly in order to improve the PDP. We suggest to follow an enactive and design thinking approach to reach this goal. We propose a first theoretical model describing the preliminary design process. The paper concludes with some considerations about the related key issues and the possible implementations and benefits.