The Capability Maturity Model (CMM)

http://www.sei.cmu.edu/cmm/cmm.html

Most companies are at Level 1. Even Microsoft is somewhere between Level 1 and 2.

Very few (less then a dozen?) companies are at Level 5; one of these is NASA.


A related topic is Cleanroom Software Engineering - http://www.sei.cmu.edu/publications/documents/96.reports/96.tr.022.html