Programmers Stack Exchange is a question and answer site for professional programmers interested in conceptual questions about software development. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Are there any differences between the Rational Unified Process (RUP) and the Unified Process (UP)? What does "Rational" mean, in this context?

share|improve this question
I thought Rational is the name of a company? – tp1 Nov 17 '11 at 20:05
up vote 4 down vote accepted

The Unified Process is a generic name for a family of process models that meet a number of criteria, such as being iterative and incremental, driven by use cases, and focus on addressing risks early. It defines four project phases: Inception, Elaboration, Construction, and Transition.

The Rational Unified Process is a refinement of the Unified Process that was created by Rational Software (now owned by IBM). It uses a series of software tools along with a process framework to define how to carry out the activities needed to run a software project, yet still provides a framework for tailoring to meet an organization's (or team's) needs.

Other refinements on the Unified Process include Scott Ambler's Agile Unified Process and the Eclipse Foundation's Open Unified Process.

share|improve this answer
It seems I started writing my answer while you were writing yours, but I posted first (didn't get the familiar notification that another answer was up while writing). Just a clarification, wouldn't dare submit and answer saying exactly the same as another answer (and in this case less). I've deleted mine, as yours is more informative (and mine a little snarky). – Yannis Nov 17 '11 at 18:32
Yeah. I got the notification that there was another answer posted as I was getting the links to the AUP and OUP. I figured since I was almost done, I was just going to post it anyway. – Thomas Owens Nov 17 '11 at 18:34

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.