This model combines iterative development with systematic aspects of the Waterfall model. It emphasizes risk analysis and management at each iteration, or "spiral," making it suitable for large, complex, and high-risk projects
SPIRAL MODEL
Determining objectives, alternatives, and constraints
PLANNING
Identifying and analyzing potential risks and deciding how to address them
RISK ANALYSIS
Developing and testing the product incrementally
ENGINEERING
Reviewing the progress and planning the next iteration.