A Project Management Office (PMO) is a group or department within a business, agency or enterprise that defines and maintains standards for project management within the organization.

The primary goal of a PMO is to achieve benefits from standardizing and following project management policies, processes and methods. Over time, a PMO generally will become the source for guidance, documentation, and metrics related to the practices involved in managing and implementing projects within the organization. A PMO may also get involved in project-related tasks and follow up on project activities through completion. The office may report on project activities, problems and requirements to executive management as a strategic tool in keeping implementers and decision makers moving toward consistent, business- or mission-focused goals and objectives.

A PMO generally bases its project management principles, practices and processes on some kind of industry standard methodology such as PMBOK (Project Management Body of Knowledge) or PRINCE2 (Project in Controlled Environments). Such approaches are consistent with the requirements related to ISO9000 and to government regulatory requirements such as the US Sarbanes-Oxley (SOX) program.

How a project management office (PMO) is designed and staffed for maximum effectiveness depends on a variety of organizational factors, including targeted goals, traditional strengths and cultural imperatives. There are three basic organizational styles for a project management office.

1.     The project repository: This model occurs most often in organizations that empower distributed, business-centric project ownership, or enterprises with weak central governance. The project office simply serves as a source of information on project methodology and standards. Project managers continue to report to, and are funded by, their respective business areas.

2.     The project coach model: This model assumes a willingness to share some project management practices across business functions and uses the project office to coordinate the communication. Best practices are documented and shared and project performance is monitored actively. The PMO in this model is a permanent structure with staff and has some supervisory responsibility for all projects.

3.     The enterprise project management office: This model also assumes a governance process that involves the project office in all projects, regardless of size, allowing it to assess scope, allocate resources and verify time, budget, risk and impact assumptions before the project is undertaken. Funding is generally a combination of direct, budgeted allocation for baseline services and a fee-for-service charge for others.