Rules and tools, and perhaps schools... that was your father's PMO.
But, that's not a great recipe these days. A better idea is given by Jack Duggal who wrote a piece for PMI recently about Reinventing the PMO
I don't think he started out to be an agilist in this article, and I'm not sure he read my most recent book on "Maximizing Project Value" (you can buy it here), but he and I are certainly of a common mind on this.
Some of the highlights are given in a post at leadinganswers on how Jack's idea apply to a PMO in an agile setting. From there, we learn these tidy bits about 'from-the-old' 'to-the-new' ideas in PMO-land:
1. From Delivery of Projects to Benefits Realization and Business Value
No longer is delivery of on-time, on-budget projects considered successful. It is necessary but not enough.2. From Delivery to Adoption and Usability
Typically, PMOs are focused on improving execution capabilities. Projects are implemented well, but often the outputs and deliverables are not used or adopted.3. From Diffused and Disjointed Focus to Holistic and Balanced Adaptive Approach
Often PMOs are pulled to address the current pain or fix the problem of the day. This results in a diffused and disjointed PMO focus and limits the ability of the PMO to provide a balanced approach.4. From Change Management to Change Leadership
Evolving PMOs understand the need for organizational and behavioural change and get involved in change-readiness assessments and preparation.
Check out these books I've written in the library at Square Peg Consulting