The purpose of the study is to investigate factors that are important for the transition from 2D to 3D by Model Based Definition (MBD). Within MBD, 3D models are used as sources of information for design, production, distribution, technical documentation, services and the overall product lifecycle. The introduction and development of MBD at Aeronautics can be described in five transitions that illustrate how knowledge enhancement from project to project and between the projects and the linear organization has evolved. The largest challenges have been in the start-up of the transitions, people are gathered with different prerequisites, seeing solutions or problems from different perspectives.