The Enterprise Unified Process (EUP) is an extended variant of the Unified Process and was developed by Scott W. Ambler and Larry Constantine in 2000, eventually reworked in 2005 by Ambler, John Nalbone and Michael Vizdos. EUP was originally introduced to overcome some shortages of RUP, namely the lack of production and eventual retirement of a software system. So two phases and several new disciplines were added. EUP sees software development not as a standalone activity, but embedded in the lifecycle of the system (to be built or enhanced or replaced), the IT lifecycle of the enterprise and the organization/business lifecycle of the enterprise itself. It deals with software development as seen from the customer's point of view.
Ambler, Scott W; Nalbone, John; Vizdos, Michael J (2005), The Enterprise Unified Process : extending the Rational Unified Process, Prentice Hall PTR, Bibcode:2005eup..book.....A, ISBN 978-0-13-191451-3, OCLC 57380579
Ramsin, Raman (2008). "Process-centered review of object oriented software development methodologies". ACM Computing Surveys. Association of Computing Machinery ACM. 40 (1): 1–89. doi:10.1145/1322432.1322435. S2CID 13604145.