【正文】 In turn, each new structural arrangement realigns the power structure and creates new tensions. The investigation of the creation or restructuring of PMOs will need to integrate the political dimension of anisational change. 5. The empirical study The methodological strategy is based upon a constructivist epistemology. Just as anisations are plex social entities, so too are the specific anisational project management structures that enpass PMOs. Our methodological strategy is designed to understand such plexity. We draw on Van de Ven’s [42] engaged scholarship, bringing together different points of view of key people involved with PMOs, and using a bination of qualitative and quantitative instruments. Four anisations have participated in the research. All have high levels of product innovation. All have at least several thousand employees and have highly developed project management methods and practices. They are from different economic sectors. Both qualitative and quantitative data were gathered from pany documents and systems and from interviews. The data collection covered the period from before the implementation of the first PMO to end of the study in 2021. It was important to cover a sufficient number of years for the history and the evolution of the PMOs to be revealed. The time period under investigation in each of the four anisations was respectively 12,10,8 and4 years. As was expected from the survey results, each anisation reconfigured its PMOs every3 to4years and sometimes sooner. The unit of analysis is the anisational transformation around an implementation or a reconfiguration of a PMO. The sample is made up of eleven ‘‘a(chǎn)nisational transformations”: four cases of implementing first PMOs and seven cases of reconfiguring existing PMOs. The anisational transformations have been modelled using a framework based on conditions, action/interaction and consequences proposed by Strauss and Corbin [43]. These three elements form a process that repeats itself, consequences being the conditions for the next iteration. In this approach, the PMO in one period is seen as a temporary state resulting from previous conditions and generating new consequences. This sequence constitutes the PMO structuring process, which is illustrated in Fig. 1. 山東建筑大學(xué)畢業(yè)設(shè)計外文文獻及譯文 9 The conditions that lead to an anisational transformation have been grouped under four themes: events from the surrounding social system, internal events, the philosophy of management and tensions to be resolved. The action/interaction element corresponds to the structuring itself. New tensions are among the consequences of the restructuring. Other consequences exist but the focus here is on the new tensions that are created. . Conditions From, the four conditions that give rise to a specific structure, the first two, social system events and internal events, are themes drawn from the social innovation framework. A good example of conditions related to the social system can be found in the telemunication case study with the major turbulences caused by the bursting of the dot bubble in 2021. In ten of the eleven transformations under study, changes in the PMO coincide with changes in senior management. In all eleven transformations, changes in the structure coincide with changes in the ‘‘philosophy of management,” expression used by interviewees. The philosophy of management can be relative that of one individual, of the top management team or of the whole anisation. A new philosophy of management usually initiates a new restructuring process, the current structure not being coherent with the new philosophy of management. For example, in one of the transformations the philosophy changed from one supporting entrepreneurship to one supporting tight controls and improved performance particularly on schedule. A new PMO manager with a vision of the PMO as exercising strong centralized control was put in place and project management was centralized from several 山東建筑大學(xué)畢業(yè)設(shè)計外文文獻及譯文 10 decentralized PMOs into one PMO. This situation imposes strict control in the management of projects where project managers were playing the role of controller. A high value is placed on transparency. Any deviation from plans should be reported and corrective action immediately identified and applied. The personal incentives of the PMO manager are linked to this: no project is allowed to pass directly from green to red! Tensions (between individuals, between substructures, etc.) emerge generally fro m disforts that get constructed over time within a specific structure. The word tension is used here in its abstract sense to describe a difficult situation that threatens to break apart (Robert Dictionary).Tensions often build up slowly until a breaking point is reached at which time a change in the structure will take place modifying or eliminating the source of tension. From the previous example, one of the consequences of the implementation of the new centralized PMO was the creation of tension related to transparency and the information provided by the product line manager: ‘‘It actually goes against the goals of most people in positions of authority in the various product units because they are held accountable for every decision, all the time, all the projects. If you’re fortable with that you have no ability to bend the truth or mask any information or try to fix something quietly for a week or two. Now everything is always posted on the website, it’s updated every week. The track of projects is always there.”(verbatim from an interview) . Resulting structure The resulting PMOs have been described using variables measuring their structures, the importance of functions performed and their resulting contributions to anisational performance. The object of this paper is not to