This new core guidance from OGC describes why, when and how to use portfolio, programme and project Offices (P3O) models. It describes what a P3O is, defining the two key types of P3O, and goes on to answer the question posed by Senior Management: "Why have P3Os and what value-add do they bring to the organisation?" It also includes business cases, funding models for set-up and ongoing costs and performance measures.The publication looks at the lifecycle of a P3O and describes the use of a project based approach to scoping and setting up a suitable P3O model within an organisation. It also includes checklists for start-up, continuous improvement, and reviving and closing down temporary offices and looks at the functions and services carried out within a P3O, and the techniques and tools used to facilitate this.Key features:* Facilitates Senior Management awareness of the status of its agenda for business change* Consistent with OGC's Common Glossary* Includes real world examples and case studies* Outlines roles and responsibilities for functions within a P3O* Contains example business cases for permanent and temporary forms of P3O* Includes sizing and tailoring guidelines* Glossary - definitions of acronyms and terms* Contains a list of online resources for good practice including templates and examples.