Authors associate the PMO with an increase in the success rate of projects, reduce overall costs, and delivery time. Which explains why firms replicate and modify it while adopting project-based structures and strategies. PMOs in different organizations hold little similarities with each other. Staffing the PMO is an overhead cost to projects, and seeking to optimize resources organizations tend to allocate more functions to them. As a result, there is a broad range of activities a PMO can perform. This study found in literature 36 different functions associated with this structure. Agile and traditional project management methodologies have fundamental differences in both planning and operational organization. Agile argues that overhead costs, requirements elicitation, and planning processes result in overspending and delaying innovative product development. These differences conflict with previously established roles, functions, and, more problematically, the people that perform them. In this sense, the introduction of agile ways of working is a disruption of traditional practices in the organization. The change to agile methods has effects of various aspects of a firm’s organizational structure, including the PMO, a symbolic figure from traditional project management. Agile standards have different approaches to the use of a PMO, and it is not clear whether the PMO in agile has similar roles and responsibilities as the PMO in traditional methodologies. This study proposes to investigate the impact of the transition from traditional project management to agile on the PMO to address this gap. The main research question makes it explicit: “How do the roles of Project/Program/Portfolio Management Offices change with the introduction of Agile methodologies to a large number of teams?” This study adopted a descriptive exploratory approach to answering this question. The study observed the changes in the roles of the PMO before and after implementations of agile with four case studies. The research conducted semi-structured interviews and applied surveys with nine professionals in these different companies. The contribution to science of this study is twofold. First, it contributes to the description of the PMO, enriching the field towards a unified theory of project management. Second, it provides empirical evidence for the changes in roles of the PMO with the introduction of agile. This study found that there are wide disparities between the roles of the PMOs in different organizations. It also found that PMO performs different functions before and after the introduction of agile methods in a firm. It seems to be consistent that the PMOs are involved in the activities of monitoring, controlling, and standardizing project methodologies in both periods. A common theme across the participants' reports is that the PMOs participation got diminished or repurposed to a supporting and serving role with the introduction of agile. An explanation for this change is the shared responsibility the PMOs have with the agile teams on processes they were the sole or main responsible in traditional settings. Another common theme is the interfacing part the PMO plays, bridging traditional sectors and agile sectors of the firm. Participants in all firms believe the current state of the PMO is not final and expect it to continue to change. Disclaimer: This research was supported by Accenture B.V.