||When planning to develop corporate real estate, Corporates have to choose between different forms of organization and sourcing. The choice of the most suitable form is a crucial decision and often problematic for companies and their corporate real estate management. Different forms like multiple prime contracts, general constructor or partnership based development forms differ with regard to their advantages, disadvantages and requirements for realization. In this context the purpose of this paper is to develop a decision support tool which helps Corporates to maximize their project outcome, project success and, in the long-term, to optimize their real estate portfolio when developing new corporate real estate. To form a scientific basis firstly relevant objectives and requirements in decision-making processes from literature research will be presented. Secondly these decision-making processes and existing tools for comparable situations in literature will then be analyzed. Thirdly the deduced model, which shows the framework for decision-making from literature, is evaluated with a case study and aggregated to specific decision-making criteria from the CREM point of view. The underlying case study was a real estate development project for a German Corporate.As a result 15 criteria, relevant in decision-making processes of Corporates, can be identified. On this basis, a model is chosen from decision theory, which supports the solution of such decision problems. This decision support tool sums up all decision criteria for CREM in a structure for the first time and will allow Corporates to structure their decision-making process for real estate development projects and will help to make them more transparent.