1. Requirements Planning Tasks: users, managers, IT staff, etc. discuss and agree on business needs, project scope, constraints and system requirements. This phase ends when the team agrees on the key issues and obtains management authorization to continue.

2. User Design Tasks: users interact with each other, models and prototypes are built (represent all system processes, outputs and inputs) and conduct intensive meetings.

3. Construction Tasks: where the system is actually built (coding, integration etc.) and users are still able to make changes or improvements for the system to meet their needs.

4. Cutover Tasks: testing, and user training. The entire process is compressed as a result, the new system is built and placed in operation much sooner.

Spell: Systems Analysis & Design, Chp. 4 - Requirements Engineering