Reengineering
 
 
Periodically project managers should set aside some time to re-engineer part or all of the system 
- The extent of this work can vary considerably: 
- Cleaning up the code to make it more readable. 
 - Completely replacing a layer.
 - Re-factoring part of the design. 
 
 - In general, the objective of a re-engineering activity is to increase maintainability.