Whilst the whole purpose of the project is to change the organization in some way, projects themselves are vulnerable to change. There are many kinds of changes and many reasons why they cannot always be avoided. Changes are usually thought of as unwelcome and disruptive, but change is not necessarily bad. Some changes need neither managing nor any of the procedures outlined in this chapter. That statement could have some project management purists throwing up their hands in horror, or rushing for their tranquillizer pills. But a moment's thought and a simple example should restore calm in the camp. The converse of this argument suggests a definition of changes that do demand a special management procedure. These are changes to any specification or other document already approved and issued to authorize work. Isochron points out that treating a project as a contract between the project team and the organization opens up a vast area of expertise for managing change.