||More and more municipalities have opted to establish a more centralized real estate management. This means that in these municipalities there is one real estate management organization. Since 1995 the number of municipalities that have centralized has increased from 18 (K et al 1995) to 34 percent in 2008 (A et al 2008). In 2009 69 percent of large municipalities (> 75,000 inhabitants) have a centrally organized real estate management (T & S 2010). This should lead to a more efficient and effective real estate decision making, resulting in more strategic opportunities for a real estate contribution to the spatial developments and social policies in the city. Centralization of real estate does not automatically ensure that municipalities act more strategically on this matter. Research has shown, when comparing six municipalities, three main reasons why they do not act more strategically: (1) not enough consistency between the urban vision and the real estate strategy, (2) no financial performance indicators in the capital goods section of the BBV and (3) information for a proper and sound decision making not timely, incomplete and inaccurate. In this research, we have developed and (experimentally) used a prototype municipal real estate decision support system (PRE-system) with Rotterdams’ development Board OBR to enhance their effectiveness and efficiency. Since the decision to centralize the management of the municipal property at the OBR in 2006, the department is professionalizing. In 2009, the centralization is officially completed and OBR published the long-range perspective Rotterdam Real Estate (MPRV) 2009-2012. The purpose of this decision support system is the operationalization of the MPRV (in a computer) in such a manner that (alternative) strategic real estate decisions can be analyzed and assessed in order to achieve social goals with minimal real estate means”. The prototype is based on three assumptions. The first is a framework for designing accommodation strategies to align the dynamic demand for real estate with the static supply on both portfolio and object level (J et al., 2009). The second assumption is the four stakeholder perspectives in Corporate and Public Real Estate Management (H en V, 2004), that of the policy maker, the controller, the user and the technical manager. The third and last assumption comes from the systems approach. In particular, the multi-actor goal oriented systems approach (L, 1998). In this approach the management of an organization is primarily seen as directed to - interdisciplinary – problem solving (the tasks). This means that the various interested organizations, both within and OBR and elsewhere (other departments) can provide input for the MRE system, and communicate with each other about the possible (combinations of) decisions. The prototype PRE-system is ready and tested in two districts in Rotterdam. This paper reports on the development, use and evaluation of the Municipal Real estate decision support system. The paper will focus on the role this system can play in integral (multi-actor) management and decision making on real estate portfolios of municipalities as well on the level of content as organization.