There a a lot of techniques and tools, for example:
-Performance measurement compared to baseline.
-Looking for defects and variations.
-Identify the root causes of problems.
-Identify the need of recurring planning.
-Work with the changes control committe.
-Customer satisfaction evaluation.
-Use metrics reports to fix problems.
-Use hitos for schedule control.
6 Repair or defects
Implement corrective, preventive and approved actions in order to repair defects.
7 Closing of the project
Closing the project if it has been completed or canceled.