Editing Capability Maturity Model (section)

==History==
{{Synthesis|section|date=August 2016}}

===Prior need for software processes===
In the 1980s, the use of computers grew more widespread, more flexible and less costly. Organizations began to adopt computerized information systems, and the demand for [[software development]] grew significantly. Many processes for software development were in their infancy, with few standard or "[[best practice]]" approaches defined.

As a result, the growth was accompanied by growing pains: project failure was common, the field of [[computer science]] was still in its early years, and the ambitions for project scale and complexity exceeded the market capability to deliver adequate products within a planned budget. Individuals such as [[Edward Yourdon]],<ref name=yourdon89msa>{{cite book
 |last1=Yourdon
 |first1=E.
 |title=1989. Modern Structured Analysis.
 |location=New York
 |publisher=[[Prentice Hall.]]
 |year=1989
 |isbn=978-0135986240
 |url-access=registration
 |url=https://archive.org/details/modernstructured00your
 }}</ref> [[Larry Constantine]], [[Gerald Weinberg]],<ref name=weinberg92qsm>{{cite book
 |last1=Weinberg |first1=G. M. |author-link1=Gerald M. Weinberg
 |title=Quality Software Management: Anticipating Change. Vol. 1: Systems Thinking.
 |location=New York
 |publisher=[[Dorset House Pub.]]
 |year=1992
 |isbn=978-0-932633-72-9
}}</ref> [[Tom DeMarco]],<ref name=demarcolister97wwb>{{cite book
 |last1=DeMarco |first1=T. |last2=Lister |first2=T.
 |title=Waltzing with Bears: Managing Risk on Software Projects
 |location=New York
 |publisher=[[Dorset House Pub.]]
 |year=1997
 |isbn= 978-0-932633-60-6
}}</ref> and [[David Parnas]] began to publish articles and books with research results in an attempt to professionalize the software-development processes.<ref name="McKay"/><ref>{{Cite news|url=http://pep-inc.com/2011/01/23/cmmi-six-sigma-their-roots/|title=CMMI-Six Sigma, their roots|date=2011-01-23|work=Process Enhancement Partners, Inc.|access-date=2018-05-11|language=en-US}}</ref>

In the 1980s, several US military projects involving software subcontractors ran over-budget and were completed far later than planned, if at all. In an effort to determine why this was occurring, the [[United States Air Force]] funded a study at the Software Engineering Institute (SEI).

===Precursor===

The first application of a staged maturity model to IT was not by CMU/SEI, but rather by [[Richard L. Nolan]], who, in 1973 published the [[stages of growth model]] for IT organizations.<ref>{{Cite journal | last1 = Nolan | first1 = R. L. | title = Managing the computer resource: A stage hypothesis | doi = 10.1145/362280.362284 | journal = [[Communications of the ACM|Comm. ACM]] | volume = 16 | issue = 7 | pages = 399–405 | date=July 1973 | s2cid = 14053595 | doi-access = free }}</ref>

[[Watts Humphrey]] began developing his process maturity concepts during the later stages of his 27-year career at IBM.<ref>{{Cite web|url=http://resources.sei.cmu.edu/library/asset-view.cfm?assetid=5329|title=People Capability Maturity Model (P-CMM) Version 2.0|website=resources.sei.cmu.edu|date=30 June 2001 |access-date=2017-01-17}}</ref>

===Development at Software Engineering Institute===
Active development of the model by the US Department of Defense Software Engineering Institute (SEI) began in 1986 when Humphrey joined the [[Software Engineering Institute]] located at Carnegie Mellon University in [[Pittsburgh, Pennsylvania]] after retiring from IBM. At the request of the U.S. Air Force he began formalizing his Process Maturity Framework to aid the U.S. Department of Defense in evaluating the capability of software contractors as part of awarding contracts.

The result of the Air Force study was a model for the military to use as an objective evaluation of software subcontractors' process capability maturity. Humphrey based this framework on the earlier [[Quality Management Maturity Grid]] developed by [[Philip B. Crosby]] in his book "Quality is Free".<ref name=crosby79qif>{{cite book
 |last1=Crosby |first1=P. B. |author-link1=Philip B. Crosby
 |title=Quality is Free
 |url=https://archive.org/details/qualityisfreeart00cros |url-access=registration |location=New York
 |publisher=[[New American Library]]
 |year=1979
 |isbn=0-451-62247-2
}}</ref> Humphrey's approach differed because of his unique insight that organizations mature their processes in stages based on solving process problems in a specific order. Humphrey based his approach on the staged evolution of a system of software development practices within an organization, rather than measuring the maturity of each separate development process independently. The CMMI has thus been used by different organizations as a general and powerful tool for understanding and then improving general business process performance.

Watts Humphrey's Capability Maturity Model (CMM) was published in 1988<ref>{{Cite journal | last1 = Humphrey | first1 = W. S. | author-link1 = Watts Humphrey | title = Characterizing the software process: A maturity framework | doi = 10.1109/52.2014 | journal = [[IEEE Software]] | volume = 5 | issue = 2 | pages = 73–79 | date=March 1988 | s2cid = 1008347 | url = http://www.sei.cmu.edu/reports/87tr011.pdf }}</ref> and as a book in 1989, in ''Managing the Software Process''.<ref name=watts89msp>{{cite book
 |last1=Humphrey |first1=W. S. |author-link1=Watts Humphrey
 |title=Managing the Software Process
 |year=1989
 |location=Reading, Mass.
 |publisher=[[Addison-Wesley]]
 |series=SEI series in software engineering
 |isbn=0-201-18095-2
}}</ref>

Organizations were originally assessed using a process maturity questionnaire and a Software Capability Evaluation method devised by Humphrey and his colleagues at the Software Engineering Institute.

The full representation of the Capability Maturity Model as a set of defined [[process area]]s and practices at each of the five maturity levels was initiated in 1991, with Version 1.1 being published in July 1993.<ref name=sei93cmm/>
The CMM was published as a book<ref name=sei94cmmBook/> in 1994 by the same authors Mark C. Paulk, Charles V. Weber, [[Dr Bill Curtis |Bill Curtis]], and Mary Beth Chrissis.

=== Capability Maturity Model Integration ===
The CMMI model's application in software development has sometimes been problematic. Applying multiple models that are not integrated within and across an organization could be costly in training, appraisals, and improvement activities. The [[Capability Maturity Model Integration]] (CMMI) project was formed to sort out the problem of using multiple models for software development processes, thus the CMMI model has superseded the CMM model, though the CMM model continues to be a general theoretical process capability model used in the public domain.<ref>{{Cite book|url=https://books.google.com/books?id=NJ0Apk1iNDAC&q=The+Capability+Maturity+Model+Integration+%28CMMI%29+project+was+formed+to+sort+out+the+problem+of+using+multiple+models+for+software+development+processes%2C+thus+the+CMMI+model+has+superseded+the+CMM+model%2C+though+the+CMM+model+continues+to+be+a+general+theoretical+process+capability+model+used+in+the+public+domain&pg=PA486|title=Juran'S Quality Hb 6E|last=Juran|date=2010-08-26|publisher=McGraw-Hill Education (India) Pvt Limited|isbn=9780071070898|language=en}}</ref>{{Citation needed|date=March 2012}}<ref>{{Cite book|title=Proceedings of the International Conference on Transformations in Engineering Education|last=Natarajan|first=R|publisher=Springer|year=2015}}</ref>

In 2016, the responsibility for CMMI was transferred to the Information Systems Audit and Control Association (ISACA).  ISACA subsequently released CMMI v2.0 in 2021. It was upgraded again to CMMI v3.0 in 2023.  CMMI now places a greater emphasis on the process architecture which is typically realized as a process diagram. Copies of CMMI are available now only by subscription.

===Adapted to other processes===
The CMMI was originally intended as a tool to evaluate the ability of government contractors to perform a contracted software project. Though it comes from the area of software development, it can be, has been, and continues to be widely applied as a general model of the maturity of ''process'' (e.g., [[IT service management]] processes) in IS/IT (and other) organizations.