The advantages of project management have been well documented, but project failure rates still remain high. This suggests continued exploration of new process models and organization structures to nurture strong project performance. One important candidate for improvement in this ongoing journey is the project management office (PMO). This paper is based on a two-year empirical study that investigated the establishment and use of PMOs and the environmental conditions in which they operated. It also identified and assessed an array of PMO functions and services and their influence on reported project performance. The core results were generally favorable toward the utilization of such features, with project standards and methods showing the highest correlation to performance in each of the two distinct populations.