Integration management should be viewed as the overarching knowledge area, or the umbrella knowledge area, under which all of the other knowledge areas exist.
There is a macro and a micro aspect to project integration management. The macro level considers how the project fits with the organization, the community, and the constantly changing environment. The micro level considers how the project constraints are balanced, project change management, configuration management, and keeping the plans updated and communications current.
Configuration Management helps us to manage the product plan, including scope and features, as progressive elaboration occurs. The Configuration Management Plan, part of the Integrated Project Plan, provides version control of the product of the project. It includes an Integrated Change Control process which facilitates the progressive elaboration process by maintaining snapshots of the picture, or level of elaboration, at any given time for the product of the project.
Some of the principles of Integration Management include the concept that the project manager should let the project stakeholders know what the process for handling changes should be in advance of the project work shifting into high gear. Changes should be decided upon and integrated into the project plans.
The project manager must be strong to filter out unwanted changes, patient in educating stakeholders on the implications of their desired changes, brutal in holding off changes that will distract from the priorities, and open in allowing process and product improvement ideas in when they enhance those priorities.