The Netherlands currently suffers from a housing shortage, which cannot be solved by the traditional project-based approach of realizing new homes. Under a visible trend of a project-transcending, programmatic approach within the construction sector, various housing associations, municipalities and market parties are united in an inter-organizational collaboration to combat the shortage of social rental housing. These have led to various regional social housing construction programs, the Bouwstroom (Dutch translation for construction flow). Since program management requires an appropriate approach for each specific program, there is a need to better understand and further develop the current application of this management concept in the Bouwstroom programs for this context. Program managers should guard against a too one-sided focus on either control management, because this is too robust for a programmatic collaboration, or interaction management, because this leads to too slow progression and expensive ideas. The solution is to complement the two approaches with each other, in which an appropriate ratio of both approaches is context-dependent. To counter interaction or control related challenges, mixed strategies should be applied over time and a right structure is necessary in the organization. Furthermore, the literature speaks of six attributes of effective program management: 1) the vision, 2) priority focus, 3) planning framework, 4) governance, 5) coordination and 6) adaption. These attributes must be applied appropriately for each program for program management to function effectively. Two representative case study programs, WoonST and Bouwstroom Noord, are analyzed. A cross-case study has made it clear that the current application of program management in both cases leads to external interaction challenges in particular. Where the internal parties are aligned and motivated, there is still a hindrance from parties that are not part of the Program Management Office, but still influence the course. This results in the municipalities being limited in their role to speed up the processes. In order to create more value of the programs, the major challenges need to be mitigated. Multiple interaction-type strategies suggested from the literature are validated to mitigate them, several of which have not been applied before. However, they still need to be balanced with control strategies, of which those proposed from the literature mostly score poorly. This indicates that the need for additional complementary control measures is still present and does not seem to be satisfied by the study's findings. This study confirms the theory that program managers should maintain an appropriate interaction and control focus, despite a short-term detriment to the process. In addition, this research shows that program managers must continue to learn. By analyzing strategies from your own program, programs from other Bouwstroom programs and even programs from different contexts, and reflecting on a specific context, unique challenges can be approached more accurately. New strategies should be learned in order to approach unique challenges more accurately.