Increasing complexity of today's buildings requires a high level of integration in the planning process. Common planning strategies, where individual project partners cooperate mainly to exchange results, are not suitable to jointly develop project goals and objectives. Integrated planning, a more holistic approach to deal with complex problems, is based on a high degree of communication among team members and leads to a goal oriented cooperation. This paper focuses on the application of an advanced groupware approach suitable to support efficiently an integrated design process in construction. First an appropriate planning process model will be presented, which differs from common product model approaches and takes into account the great importance of team- and goal orientation in integrated planning. Then the idea of an open CSCW platform is proposed, which basic structure and containing elements are based on the defined planning model. Appropriate cooperative planning scenarios can then be ad-hoc modeled and configured dynamically on this CSCW platform according to the requirements of the specific project. For the participants of the planning process, the resulting groupware approach represents an integrated computer based working environment. This environment allows a kind of immersion into the project. Finally a prototypical implementation of this approach will be shortly discussed.