Change is an inevitable part of a project. During the lifetime of a project, particularly larger projects, there will often be a request for change, whether to budget, timeline, quality, or scope.
Each stage is broken down into individual pieces of work or work packages often managed by Team Leads. If tolerances to those work packages are breached (i.e. some part of the product is going to cost more than expected) it is reported to the Project Manager. The Manager may choose to report this to the Project Board and make a change request.
Change requests can also come at the end of stages (where tolerances are also set) which are required to be reported to the Project Board. When the Project Manager issues a change request it is logged in the Issue Register.