Barry Boehm is known for four main contributions to software engineering. He was the first to identify software as the primary expense of future computer systems, he developed COCOMO, the spiral model, and pedegogy.

In an important report to DARPA (year?), Boehm predicted that software costs would overwhelm hardward costs. DARPA had expected him to predict that hardware would remain the biggest problem, encouraging them to invest in even larger computers. The report inspired a change of direction in computing.

Table of contents
1 Software economics
2 Spiral model
3 Career
4 Awards

Software economics

Barry Boehm's book Software Engineering Economics 1981, Prentice-Hall ISBN 0-13-822122-7 documents his Constructive Cost Model (COCOMO). It relates software development effort for a program, in man-years T, to source lines of code (SLOC).

For a single software developer, k can be factored out by using more than 1 SLOC data point. In this case, x can be a fraction like 0.1 or 0.25.

  • Note: since programmers are not interchangeable parts, Brooks' Law applies:
    • Adding programmers to a late project makes it later.
    • Thus this formula is best applied to stable software development teams which have completed multiple projects.

Spiral model

Boehm also created the spiral model of software development, in which the the phases of development are repeatedly revisited. This iterative software development process influenced extreme programming.


Boehm has worked as educator and researcher for many years. Boehm worked at RAND, TRW, Inc, DARPA, and is currently TRW Professor of Software Engineering, Computer Science Department, and Director, USC Center for Software Engineering.


Recent awards include the Office of the Secretary of Defense Award for Excellence (1992), the ASQC Lifetime Achievement Award (1994), and the ACM Distinguished Research Award in Software Engineering (1997). He is an AIAA Fellow, an ACM Fellow, an IEEE Fellow, and a member of the National Academy of Engineering.