Listing the Unified Process (UP) here as an agile development process is not entirely correct. Compared with the other processes, the Unified Process is a descriptive process rather than an empirical one. That means the UP describes in text, like a hyperlinked version of a book, what particular roles are required to do, when they do it, and how they do it. As with any book, changes to it are more challenging to redistribute. Although the Unified Process is based on architecture-centric, iterative-incremental development principles, the project phases, disciplines, and relationships between roles and responsibilities provide less flexibility. On the other hand, it is exactly the somewhat fixed description of the process that appeals to large organizations that need to comply with a variety of standards and need to outline, for example, a companywide policy for a software development process. Nonetheless, the UP provides a tremendous step forward from the traditional waterfall process (large, separated, and sequenced software engineering phases) and is often an intermediate step between traditional processes and agile processes. There are two noteworthy flavors of the Unified Process:

1. IBM Rational Unified Process (RUP)

The RUP is a result of merging three methodologies (Booch, Objectory, and OMT) during the early and mid-1990s into one unified approach. After Rational was acquired by IBM in 2003, an eclipse-based1 process authoring tool called the IBM Rational Method Composer (RMC) was developed. The eclipse framework provides a consistent platform for all toolmakers to develop and deploy software products. By using such a framework, developers can organize different tools under one umbrella and view them through perspectives. Therefore, RUP can easily be modified using the RMC.

2. OpenUP

OpenUP is an open-source process released in October 2006. A year earlier, IBM Rational donated a significant amount of its “RUP for Small Projects” to the eclipse community (which you can learn more about at with the goal of developing a simple iterative-incremental process framework for small projects. Like the commercial version of RUP, OpenUP comes with an eclipse-based free process authoring tool called the Eclipse Process Framework (EPF).