Projects with internal vs. external customers: An empirical investigation of variation in practice

• Internal and external projects form different configurations.
• Their organisational contexts and project characteristics form coherent patterns.
• Project management practices are adapted to these specific contexts.
• The determinants of performance are different in each configuration.
• Up to 47% of variation in performance is accounted for.

The purpose of this paper and the research programme of which it is part is to empirically investigate variations in project management practice. The research is based on the analysis of an extensive dataset containing information on the extent of use of a large number of practices and contextual variables related to organisational contexts and project characteristics. The paper focusses on the effects of the difference between projects with internal and external customers, which have been shown to be an important characteristic of the project context. A distinction is made between the extent of use of project management practices and the effect of variation in the extent of use on project performance, which are shown to be very different both conceptually and empirically.