This picture illustrates state models of the change requests of three different types:
- Standard Change;
- Normal Change;
- Emergency Change.
Also, you can find a brief description of every state under the picture.

States Description
Registered
This state is for the newly created change requests. If this is a Standard change, then it transitions straight to the In Progress state, as the Standard is a pre-approved type. If this is a Normal or Emergency change request, then the request transitions to the Authorization state. Also, in case of a Normal Change, this step can be skipped, and the Authorization state can be assigned right away.
Authorization
This state is mandatory for Normal or Emergency Changes. In this state, the request must be reviewed and authorized by the responsible persons or groups (see more on the Change Request Authorization). After all authorization steps have been passed, the change request transitions to the Scheduled state.
Scheduled
In this state, the change request has the following prerequisites:
- Planned start date;
- Planned end date.
So it is preliminary known when the change will be implemented.
In Progress
This state displays that the request is in progress of implementation now. When the work is over, the state has to be changed to the Completed.
Completed
After the work is over and the request is transited into this state, the requester can perform the tests and give feedback by the results of the implementing. After this, change the state to the Closed.
Post-Implementation Review
When the request is completed (whether successfully or not), the Change Advisory Board has a right to perform Post-Implementation Review on the basis of the implementing. It is a good practice that allows gaining the "lessons learned" after the implementation, especially if there were any issues on the way.
For this, the change request state must be changed to the Post-Implementation Review state from the Completed state. After the review, similarly to the Completed state, mark it as Closed.
Closed
All activities on this change request are over, and it cannot be reopened.