PSP history and purpose – lecture notes


Quality Mgmt is a recent invention (since 1900's).

Necessitated by industrial revolution.

Before that, craftsman learned under supervision of a mentor.

With industrial revolution mass production reduced value of individually crafted products. Old approach doesn't work when goal is to produce large quantities of identical product.

Henry Ford is frequently cited as American pioneer of industrial process mgmt.

Less well known is Walter Shewhart. Statistician. Realized you could apply statistics to industrial processes to obtain quantitative methods for controlling quality.

W. Edwards Deming – major figure in Quality Mgmt. Student of Shewhart's. 1927 at Bell Labs. Broadened Shewhart's specific techniques into an entire mgmt philosophy. He worked as statistical advisor to U.S. Census dept. His first big success was during WWII when he contributed to creating standards for military equipment and munitions production.


Oddly, this approach was not adopted by the private sector after WWII. Overseas demand for U.S. goods was so huge, quality didn't matter.


After WWII Deming went to occupied Japan to assist with Census.

Japanese had heard of Shewhart and were trying to use his techniques, so when a living breathing student of Shewhart appeared they implored him to teach them. Deming talked to hundreds of engineers and managers.

His message: “Improving quality will reduce costs while improving productivity.” It doesn't cost more to produce high quality products. If you start at the beginning, quality reduces costs.


Many Japanese manufacturers had significant success with his methods and soon Japanese products were being recognized worldwide as inexpensive AND high quality. Deming became a national hero in Japan – often considered to have more influence on Japan business and manufacturing than any other non-Japanese person.


He returned to U.S. But his work was largely unknown.


In the 70's Japanese cars were becoming competitive with U.S. Autos.

Ford goes to Japan, asks how they do it and they say “Your guy, Deming taught us.” Ford asks “Who is this Deming guy. Find him.”

Ford goes with Deming's ideas, in the 80's Deming was significant force in overhaul of Ford mgmt philosophy, and in '86 Ford became the most profitable U.S. Auto company.


Deming dies in 1993. His students continue his teachings “Quality Management” is now standard management teaching.


Computers. At IBM, in early 80's was costing them more to build their own chips than import them from Japan. Applying Deming ideas made dramatic improvements. Also in installing machines in the field.


Enter IBM exec Watts Humphrey. He believes Deming's work can apply to software. He and others created Capability Maturity Model (CMM). Worked well for organizations. Many government contracts required bidders to have achieved level 3. As of 2012, only 10 US companies achieved level 5.
CMM Framework

He realizes you need good code from individuals. He scales down the CMM for individuals, called PSP.


SEI publishes / owns. Offers certifications.


Humphrey died in 2010. Extensive Interview for Computer History Museum.