The Mythical Man-Month
Frederick P. Brooks. Addison-Wesley, 1975, .
The classic book on the human elements of software engineering. Software tools and development environments may have changed in the 21 years since the first edition of this book, but the peculiarly nonlinear economies of scale in collaborative work and the nature of individuals and groups has not changed an epsilon. If you write code or depend upon those who do, get this book as soon as possible. You (and/or your colleagues) will be forever grateful.
This book has been mentioned in the following pages of the Jargon File: Brooks's Law, second-system effect.