Should one nominate an internal or external project manager?

The objective of this paper is to examine the differences in performance between internal and external PMs and to identify the advantages and disadvantages of each employment type. An organisation that employs project managers (PMs) must consider which is better: an internal or an external PM. Internal PMs are usually employed with a monthly salary, while external PMs get a retainer or a percent of the project budget. The paper used a multi-criteria decision analysis model, (the super efficiency ranking method), that objectively compares the performance of PMs according to their past performance. The model was applied in a case study with 150 projects managed by 57 internal and external PMs, all executed during 2018–2021 in one water infrastructure company in Israel. The results show that the average performance of internal PMs is statistically significantly higher than external PMs.