Most of the time, requests can be handled in a direct manner such that the only relevant roles are the people who make requests and the people who fulfill them. Sometimes, obstacles present themselves and it is necessary to route the request to a specialist or decision maker, leaving the implementor free to process additional requests. Other supporting functions, such as capacity planning, need to co-exist with the installation process to help the process and systems run smoothly. Below is an outline of the identified roles.