The conceptual phase in automotive development is characterized by variant changes, alternating definitions, requirements and iterative actions, which are influenced by legislation boundaries and ergonomic tasks as well as interior, exterior and design requirements, crash and safety standards, customer demands and specific functionalities. An important factor for a successful development states an optimized interaction between the different engineering tasks based on efficient computer aided tools, methods and strategies.The project treats the development of an integrated 3D-CAD based model for the automotive concept phase. This model includes geometry elements for the visualization of vehicle exterior and interior boundary surfaces, package relevant components, legislation based restrictions and ergonomic viewpoints. A fully parametric associative control of the geometry modules is accomplished by a CAD - external data base, which enables additional functionalities in the field of template control, data tracking and release management. Besides geometry based processes, the automotive concept phase is challenged by different additional tasks based on functionalities, as there are the mass management, structural optimization, driving performance, fuel consumption and others. The implementation of product structure driven modules into the CAD based model and the definition of data interfaces for functional dimensioning enables the support of further investigations in conceptual full vehicle development. The developed methods and strategies, combining CAD design and CAE simulation tasks, are able to significantly support the concept phase in the automotive development process.