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Carnegie Mellon University | Software Engineering Institute


Watts S. Humphrey

Software Quality Award 

Nomination Period Begins: January 1, 2024 

An Outrageous Commitment, A Lifelong Mission

When Watts Humphrey arrived at the Carnegie Mellon Software Engineering Institute (SEI) in 1986, he made what he called an “outrageous commitment to change the world of software engineering.”

By all accounts, he succeeded.

During his tenure at the SEI, Watts Humphrey established the Software Process Program, led development of the Software Capability Maturity Model, and introduced the Software Process Assessment and Software Capability Evaluation methods. These later became the basis for the development of the Capability Maturity Model Integration (CMMI), a framework of software engineering best practices that has been adopted by thousands or organizations throughout the world. Humphrey also led the development of the Personal Software Process (PSP) and the Team Software Process (TSP). In 2005 Humphrey received the National Medal of Technology, the highest honor awarded by the President of the United States to America’s leading innovators.

Humphrey, 83, died on October 28, 2010 at his home in Sarasota, Florida.

“Watts Humphrey was one of the icons of software engineering--one of a handful of engineers like Barry Boehm, Fred Brooks, and Vic Basili who have helped define this young field," said SEI director and CEO Dr. Paul Nielsen. "Watts brought engineering to software engineering. His work has had immeasurable impact on the global software community, tirelessly urging the community to emphasize quality, measurement, and performance."

Known as the “Father of Software Quality” Humphrey dedicated the majority of his career to addressing problems in software development including schedule delays, cost increases, performance problems, and defects.

“He was a wonderful leader and a wonderful man. He set forth an energizing goal and an inspiring mission that we all wanted to be a part of,” said Anita Carleton, director of the SEI’s Software Engineering Process Management (SEPM) Program, who was initially hired by Humphrey. “He was my lifelong mentor and my boss.”

Born on the Fourth of July, 1927, in Battle Creek, Michigan, Humphrey credits his father—an MIT-trained engineer who later worked on Wall Street—with shaping his work ethic and approach to problem solving. Early in his school years, Humphrey struggled to read and failed first grade. His father, also named Watts, pulled his son out of school and moved the family to Litchfield, Connecticut, where his oldest son could attend a school to receive more individual instruction.

“He insisted that I didn’t fail, the school failed, and he was going to get to a school that would help,” Humphrey told interviewer Grady Booch in an interview published in early 2010 for the Computer History Museum. Humphrey, who was eventually diagnosed with dyslexia, graduated valedictorian of his high school in 1944. After high school, he deferred studying at the California Institute of Technology to serve in the United States Navy during World War II.

In the Navy, while in officer training, he was initially trained to be a radio gunner, but later was trained to take Morse code where, once again, he earned top marks.

A Lifelong Learner

After his service, Humphrey earned a bachelor’s degree in physics at the University of Chicago, studying under Enrico Fermi. He then completed a master’s degree in physics from the Illinois Institute of Technology (IIT) and an MBA degree, with an emphasis on manufacturing, from the University of Chicago. There, he later recalled, professor Judson Neff taught him the three most important things in manufacturing: planning, planning, and planning.

“He said ‘if you don’t plan, you can’t run a manufacturing operation,’” Humphrey explained. “That had an enormous impact on me.”

Cost accounting also made an enormous impact on his later work. “It’s a tremendously powerful field, the whole idea of measurement and precision,” Humphrey later explained.

After graduation, he worked full-time as director of scientific personnel for a lab that was being started at the University of Chicago while taking night courses at IIT in electrical engineering.

Early Influences

From 1953 to 1959, Humphrey worked at Sylvania in Boston.

“I was put in charge of circuit design, but I had never done circuit design,” Humphrey explained in 2009, in an interview for the SEI Library archives. “That was a marvelous early experience. I discovered that I was managing people who knew more than I did about what they were doing. The typical management view is manager knows best. Rather than fake it, I decided to spend my time asking questions. I asked people ‘How do you do that? Why are you doing that?’”

This approach, of not assuming he knew more than the people he was managing just because he was managing them, became a guiding philosophy throughout his career, Humphrey explained.

In his first year at Sylvania, Humphrey enrolled in summer courses at the Massachusetts Institute of Technology (MIT) on the Whirlwind Computer that were taught by professors from Cambridge University. It was there that he met his future wife, Barbara, who was working in the computer lab. The couple married in May 1954.

Ever the learner, Humphrey wanted to know more. He inquired about computer courses at Northeastern University.

“They didn’t have any, but they convinced me to teach one. So instead of taking a course I turned out to be the professor,” Humphrey explained. In order to prepare, he spent weeks at the Harvard and MIT libraries and put together a course on computer design. “I ended up writing a book on it,” he said. His class consisted of employees at Honeywell Corporation who spent their days building computers.

Humphrey said the experience again reinforced the philosophy that to manage or teach effectively you need to respect the knowledge and experience of those who you are managing or teaching.

“The idea of not having to know more than your students or your employees and to deal with them rationally anyway and to be a manager and to be in charge, has stood me in good stead ever since,” Humphrey said.

When Humphrey arrived at IBM in 1959, he initially worked in hardware as a computer designer and architect. He transitioned into software and became the director of programming and vice-president of technical development where he supervised 4,000 software professionals across 15 laboratories and seven countries. This transition from hardware to software management and the challenges Humphrey faced became yet another catalyst for his research into the field of knowledge work, a term initially coined in the 1970s by Peter Drucker to describe the intangible skills and know-how that many workers in information technology, as well as other fields, bring to their jobs.

“I discovered through this period that hardware management principles, while sound, weren’t effective in a software setting,” Humphrey said in an interview in early 2010. “Software is large-scale knowledge work. It’s hard to manage people when you don’t understand what those people are doing.”

Shortly before he arrived at the SEI in 1986, Humphrey wrote a much-discussed column in IEEE Spectrum, asserting that a massive, complex system—in particular the Strategic Defense Initiative—could be programmed with high quality and reliability if it were done by “strong technical teams that use a highly disciplined development process.”

An Outrageous Commitment

When he arrived at the SEI, Humphrey worked to clarify that process.

“Changing the world of anything is an outrageous personal commitment. That’s what makes it outrageous. I felt it needed to be done. I knew I couldn’t do it alone, and I wanted an environment where I could work with folks and do that,” Humphrey explained in the 2010 interview.

“Changing the world of anything is an outrageous personal commitment. That’s what makes it outrageous. I felt it needed to be done. I knew I couldn’t do it alone, and I wanted an environment where I could work with folks and do that,” Humphrey explained in the 2010 interview.

Larry Druffel, SEI director and CEO from 1986 to 1996, said that when Humphrey arrived at the SEI, he came with a vision based on his work at IBM; software could be managed by process.

“We all understood the importance of things like version control, configuration management and methodology, but I don’t think anyone knew how to put those into a transferable form,” Druffel said. “Not everybody thought that it was a good idea at the time, but he was persistent, and he was proven right. It could have died easily after several iterations. There were enough people out there criticizing it. But he stayed with it and he made it work.”

Working with a team, Humphrey identified characteristics of best practices in software engineering that began to lay the groundwork for what would eventually become the Software Capability Maturity Model (CMM) and, eventually, CMMI.

Druffel nominated Humphrey to be the first ever SEI Fellow, a designation awarded to people who have made an outstanding commitment to the work of the SEI, and who continue to advise SEI leadership on key issues.

“After we named him fellow, I said ‘Watts, you can work on anything that you want to.’ He said ‘I’ve always believed we can provide statistical control to what the individual software engineer does,’” Druffel explained.

The Beginnings of PSP and TSP

Jim Over, who now leads the TSP initiative at the SEI, said Humphrey had begun his work in bringing discipline to the individual software engineer—the basis for the Personal Software Process (PSP)— long before his appointment as an SEI Fellow.

Humphrey first tested his theories on a process that he developed for managing his personal checking account. Next, he tested this on the personal software development process by writing more than 60 small programs in Pascal and C++, Over explained. Humphrey then began working with organizations to pilot this new personal process for software engineers.

Not long after, Humphrey published his first PSP book, A Discipline for Software Engineering, and developed a course for software engineers. Over, who enrolled in the first PSP course offered at Carnegie Mellon, said it changed his career.

“When you learn how to properly measure your own performance and analyze the result in order to improve, you get real, lasting, behavioral change that leads to performance gains and improvement,” Over explained, adding that the class went from underestimating their work by about 40 percent to being within a few percent under or over estimate on each assignment. “We had a 10 times reduction in the number of defects that escaped to the unit testing phase by the end of the course. These results were unbelievable. If I hadn’t been there I would not have thought this possible.”

After the course, Over stepped down as a project leader and began working with Humphrey to transition TSP and PSP into software engineering practice. During the course of their work together, the two became close friends.

“What will stick with me? First the belief that with both the maturity model and the PSP/TSP, Watts has created a framework that is the right stuff for software engineering and probably most kinds of related work. It works. Second is the value of data. Third are all the little quotes. Watts is a master at reducing the complex to the simple, and there are hundreds of these little gems,” Over said.

  • Watts on planning: What’s the most significant factor in determining when a project will finish? When it starts. If you can’t make accurate plans, plan often.
  • Watts on producing quality work: If you want a quality product out of test, you must put a quality product into test.
  • Watts on assessment: If you don’t know where you are, a map won’t help.

During his work as an SEI Fellow, Humphrey faced many naysayers, Druffel recalled. With each critic, he would listen and adjust his approach, but never once did he give up on the idea that he could teach software engineers the skills they need to track their own work, adhere to plans, and develop defect-free software. After PSP was established, Humphrey applied those same concepts to engineering groups as part of the Team Software Process (TSP).

Today, TSP has been adopted by leading software organizations across the globe including Intuit, Oracle, and Adobe. In 2006, the SEI launched a TSP initiative with Tec de Monterrey, a leading private university in Mexico, to help Mexico become a better national provider of IT products and services. In South Africa, the University of Witwatersrand in Johannesburg is working with the SEI to pilot TSP in organizations as part of an effort to make the country’s IT sector more competitive.

“What Watts brought is an acceptance of the discipline of software engineering,” Druffel explained, “He was working on these ideas when he left IBM in 1986. Here we are in 2010 and he was still working on related concepts. That’s persistence. Most people don’t stay with something that long. He had staying power.”

Dedication to Family

As Humphrey emphasized the importance of discipline to the global software engineering community, he also talked often of the importance of family to friends and colleagues.

His daughter, Sarah Humphrey, said her father’s struggles with reading and his own father’s support shaped his work ethic at an early age.

“He loved to learn and I think the reason he loved to learn is that he had a victory over how hard it was, through the support of really wonderful people." —Sarah Humphrey

“He loved to learn and I think the reason he loved to learn is that he had a victory over how hard it was, through the support of really wonderful people. His father was a huge champion of his,” Sarah Humphrey recalled, adding that her father was a huge proponent of flash cards. If he didn’t know something, he would make a flash card for it. He had stacks of flash cards, and separated them into piles based on what he knew, items that he was still a little unsure of, and another pile for any concept that he still hadn’t mastered. “He was one of the most insanely disciplined people I’ve ever met. I used to set my watch according to what he would do in the morning, where his newspaper was, how it was folded next to the plate, the orange juice is here, the newspaper is here and that means it must be x time.”

Sarah Humphrey recalled that when she was little, her father tried to teach all of his children how to sail. During her lesson she kept refusing to take the tiller from her father.

“So he jumped off the boat and swam ashore. That was just great. I took the tiller,” she recalled. “He would always say ‘Never say I can’t. Say I can.’”

Humphrey’s seven children are Kate Humphrey Pickman, Lisa Humphrey Fish, Sarah Humphrey, Watts Humphrey Jr., Peter Humphrey, Erica Humphrey Jarrett and Christopher Humphrey. He has eleven grandchildren: Luke Pickman, Eric Fish, Jesse Fish, Colin Fish, Daniel DeCamello, Jessica Humphrey, Dorothy Humphrey, Alex Jarrett, Chris Jarrett, Charlotte Jarrett and Nicolas Humphrey Oberparleiter.

A Favorite Passage

Humphrey, with Steve Masters, was also instrumental in coordinating the first Software Engineering Process Group (SEPG) conference, which was held in Pittsburgh. The conference series, now in its 22nd year, hosts annual events in Asia, Europe, North America, and Latin America. At the conferences, it became a tradition for SEPG attendees to run with Humphrey in the mornings.

While at the SEI, Humphrey earned many accolades for his work including the National Medal of Technology, the country’s highest honor in this field. In early 2009, Humphrey was selected as an ACM Fellow by the Association of Computer Machinery, its most prestigious member category. He received an honorary doctorate of software engineering from Embry Riddle Aeronautical University, and was a member of the university’s Industry Advisory Board, and computer and software engineering departments. He was also a member of the editorial board of the Journal of Empirical Software Engineering and the journal Software Process Improvement and Practice. He is the author of 12 books, and hundreds of technical reports, journals, and columns.

“You are lucky in your life to have a person who inspires you and puts forth a world objective to excite you so much that you want to engage in that mission with them,” Carleton explained.

She keeps a copy of all of Humphrey’s books on a shelf above her desk. While talking about Humphrey and the impact that he has made on her personally, and on the field of software engineering, she pulls down A Discipline for Software Engineering to read a well-worn passage, a favorite. It’s a passage, she says, that defines Humphrey and his message. It crosses all disciplines and fields of study.

“Deciding what you want from your chosen field is like asking what you want from life. Surprisingly often, people achieve their objectives, but in ways they did not expect. Life rarely turns out the way we plan. While our carefully developed strategies may go down in flames, a new and more rewarding opportunity shows up in the ashes. The key is to keep an open mind and keep looking. In life, we all reach the same end, so we need to concentrate on the trip. Just as with a process, once you decide how you want to live, the rest will follow. Devote yourself to excellence, and you just might achieve it. That would be worth the trip.”

“That is Watts. He devoted every aspect of his life to excellence,” said Carleton. “I spoke to Watts recently, and he told me ‘My life’s work is in your hands now.’”

“He was a wonderful leader and a wonderful man. He set forth an energizing goal and an inspiring mission that we all wanted to be a part of.”

— Anita Carleton

Stories and Memories of Watts

My experience was late in life ... during my tenure as managing editor of CrossTalk. We did a long, comprehensive interview with him in June 2009. He still was in great spirits, despite the diagnosis, despite his recent treatment. It was a fascinating meeting. ~Drew Brown


I'm shocked and sad to know that Watts Humphrey is no more with us. I'm also embarrassed that I came to know about this so late. I first came across this name in my college library, I saw a thick orange cover book with an interesting title Discipline for Software Engineering during my post graduation in Software Engineering in University of Mysore. First time I came across a book which was very practical and as a student I could implement those concepts. I loved the book. The idea of improving Personal Productivity fascinated me. This is the book that has influenced me to choose my career in Software Quality and Process Improvements. Later I read all his books and started collecting them as my personal assets. I was fortunate to meet him in person and take his autograph on a book when he visited the Wipro campus in Bangalore during IEEE SPA award assessment. He asked me "Have you read this book", I replied "Of course, all your books sir". I could see a broad smile and appreciation on his face. He may not be there with us physically, but his lives with us with his ideas and the rich knowledge base he has left us. In my view, the best tribute to this extraordinary man is to implement his ideas and to take forward the field of Software Engineering. ~Raghavendra Mithare


I first met Mr. Watts Humphrey as he was supporting training for either Baldrige Examiners or TickIT I was attending in the very early 90's. We were chatting at a classroom table. When he found out I was the Director for Quality at Intergraph Corporation, at that time in history a SW/HW development firm quickly approaching Fortune 300, he produced a copy of the CMM Document, very thin at that time, I think it was v1.0 in an envelope and handed to me. Watts was very excited and energetic, the ultimate professional and gave a tremendous "sales pitch" about it and strongly recommended we use it. He could not have been more correct in his recommendation. Thanks to Mr. Darryl Davis and Mr. John Wiley (John has since passed on) we began that journey shortly thereafter. ~Frank Knight, Ph.D.


I have known Watts for many years. He was always very generous with his time. I would email him with a question to be answered in my "SPIN doctor" column in the Boston SPIN Newsletter. His responses were always prompt and right on. Through the years, we became friends - discussing software issues, solutions, how TSP and the CMM fit together. Watts always encouraged Donna Johnson and I (LOGOS International) to continue our research into the problems facing small projects, organizations and companies who ventured into the CMM/CMMI world. He felt we were making an impact and encouraged us to coninue our work. This last year Watts and I have been emailing, encouraging each other to continue our writing. He was open about his situation and was positive and upbeat inspite of it. He was a unique, solid, bright, and devoted man to his field, fellow engineers, and family. He has left a huge legacy on which we can build and continue to improve our software engineering profession. Thank you Watts and I will miss our little chats. ~Judi Brodman


I had a keen interest in software process improvement after completing a masters degree in computer information systems, and studying about the Capability Maturity Model in one of the courses on the Software Lifecycle at the University of Phoenix, Denver Tech campus. Since the company I now worked for was located in Pittsburgh, I attended SEPG meetings that were held monthly at the SEI. Watts came to one of the meetings and did a presentation on PSP shortly after writing the book, "A Discipline for Software Engineering." Watts was so entertaining, energetic, and passionate about the PSP, that a work buddy (Jim McHale) bought 2 PSP books (one for him and one for me) at the CMU bookstore that week. We started doing the exercises together during lunch, and started applying the stuff to the work we did. The PSP radically changed my software engineering mindset to focus on producing high quality software, and I thank Watts for his important contribution to my profession. ~Steve Karg


We were privileged to have the participation of Watts Humphrey in November 2007 in Santiago of Chile, where he presented an important speach in SEPG LA 2007, organized by SPIN-Chile in conjunction with the SEI and the ESI. In addition to its undeniable technical skills, is necessary to emphasize its proximity to people, always in a pleasant tone and level, showing a broad willingness to teach and give advice to anyone who came near him. No doubt his departure leaves a big void, but we thank him for the successful passage through our lives.~Marisol Meneses R.


Marvelous: meaning amazingly exceptional, wondrous, or of superior quality. It is not a word that we use much these days, but Watts used it often in his stories and conversations. When we shared good news with Watts, his response was usually "marvelous." Reflecting on his life, it struck me what an appropriate word this is for Watts. The way, with the support of his father, he overcame his struggles with dyslexia was marvelous. His experiences as a young man, from serving in World War II, to his college wrestling, to his study with an eminent physicist, were marvelous. His wonderful wife and amazing family are marvelous. His love of learning and talents in teaching were marvelous. His career, accomplishments, discipline, work ethic, commitment, inspiring leadership, and gifts to our profession were marvelous. Both directly and indirectly, he improved the careers and lives of others, including mine, my wife's, and our dyslexic son's. Watts was, absolutely, marvelous. ~Darryl L. Davis


I’ve been very sad these recent days, since we won’t be able to share with Watts new challenges and successes. He touched my life not only with his teachings but with his example of commitment, enthusiasm and vitality.

I guess that you also feel deeply sad, and I hope that this sadness could soon become a joyful memory, filling us with pride and appreciation to God for letting us crossing our lives with Watts.

Unfortunately, I won’t be able to travel to Florida this weekend, but as well as I did in the past months, I will pray for him and also for his family and friends to accept and overcome his loss.
Agustín de la Maza Huesca