Behavior of internal stakeholders in project portfolio management and its impact on success

Stakeholder behavior and stakeholder management are key success factors within project portfolio management (PPM). This empirical study of 197 project portfolios investigates the effect of the intensity of engagement (IoE) of portfolio-internal stakeholders on project portfolio success. We show that the effect of stakeholders is phase-specific and that role clarity as a measure of PPM maturity affects the nature of the relationship between the IoE of stakeholders and portfolio success. The effects of the IoE of senior managers on success are not clearly positive with regard to strategic portfolio structuring and are even negative in operative portfolio steering in established PPM systems. In immature PPM systems, line managers tend to take advantage of their position in resource management. Surprisingly, the influence of portfolio managers in portfolio steering is insignificant. Altogether, this paper shows the diverse effect of the IoE of stakeholders on portfolio success. This study enriches project research by applying stakeholder theory to the project portfolio context and offers practical guidance for further professionalizing PPM.