A Survey of System Development Process Models



Typical Tasks in the Development Process Life Cycle

Process Model/Life-Cycle Variations

Ad-hoc Development

The Waterfall Model

Iterative Development


The Exploratory Model

The Spiral Model

The Reuse Model

Creating and Combining Models



The Waterfall Model

The Waterfall Model is the earliest method of structured system development. Although it has come under attack in recent years for being too rigid and unrealistic when it comes to quickly meeting customer's needs, the Waterfall Model is still widely used. It is attributed with providing the theoretical basis for other Process Models, because it most closely resembles a "generic" model for software development.

Figure 2.  Waterfall Model

Figure 2. Waterfall Model

The Waterfall Model consists of the following steps:

Problems/Challenges associated with the Waterfall Model

Although the Waterfall Model has been used extensively over the years in the production of many quality systems, it is not without its problems. In recent years it has come under attack, due to its rigid design and inflexible procedure. Criticisms fall into the following categories: