To fulfill the demand for a more sustainable built environment led to a more complex design process and a need for synergy between the architectural and engineering domain. To cope with this additional complexity architects need more support from specialized engineers. The different expertise of engineers must be used more effectively especially in the conceptual design phase to reach for new solutions. This has consequences for the role of the engineers involved; they have to operate early in the conceptual building design process and act more as designers and less as traditional calculating engineers. As a consequence engineers have to develop new skills. Also the architect has to learn to not only share his ideas in the conceptual design phase but to really open up his mind and to truly design together with the engineers. It is important that no longer the architect is the one that leads the design process but that the team of architect and engineers leads the design process: building design becomes a team effort already in the conceptual phase of design. To support these diverse multidisciplinary building design teams we developed a supportive design method in cooperation with the Dutch professional organizations of architects and consulting engineers. This design method is based on the use of morphological charts and a morphological overview. It helps architects and engineers with their new role in the conceptual design phase as it enables to structure each perspective on the design task as well as to structure the available domain knowledge. Our design method showed that it is possible to engage engineers within the conceptual building design phase and let other disciplines learn from them. After testing the method in workshops as part of a training program in industry, the design method was transferred and applied at the department of architecture for master students for their multidisciplinary master project Integral Design. In these projects student teams consisting of architects and engineers had to design net Zero Energy Buildings. In the last 9 years several master projects Integral Design were held and there was an going process to further improve the method for supporting the cooperation between architects and engineers. Our design method showed that it is possible to engage engineers and let other disciplines learn from them within the conceptual building design phase..