In a few years, Additive Manufacturing (AM) has become a promising technology and opened up new prospects for the product development. Nevertheless, design methods remain predominantly based on conventional manufacturing processes and AM capabilities need to be better mastered and integrated in the design team. This article questions how a new technology (i.e. AM) can enable product innovation. Thus to support designers in preliminary design, a methodology is introduced. The specificity of this methodology is the use of a tailored AM knowledge, i.e. a knowledge delivered to the right user at the right time and in the right format, in order to be useful and usable during the creative stages of the design process.