When it is determined by the parties in charge of the financial elements of the potential project that the project actually is going to take place and has officially been signed off on and approved, the next step is making the determination as to exactly what group, company, or conglomerate will serve for the duration of the project’s life as the official performing organization or, in the event that there are more than one group working on the project, the primary performing organization. In terms of project management, the performing organization is referred to as the specific enterprise or group that is viewed by all parties to be the one that is the most directly and explicitly involved in all phases and aspects of doing any and all work of the given and respective project. In some cases, there may be more than one designated performing organization, meaning, there may be multiple groups that are involved heavily in the workload. In such cases, typically one project team leader is designated to oversee the work of both or all organizational elements.
This term is defined in the 3rd and the 4th edition of the PMBOK.