Sterman, John , Business Dynamics: Systems Thinking and Modeling for a Complex World, Irwin/McGraw-Hill,  2000.  ISBN 0-07-231135-5. 

My first thought on reviewing this book is that it's a gift to humanity. If only business and public policy were set using the methods described, we'd have a much more productive and prosperous society ... with a lot less misery. It's excellent and just over $123 from Amazon.com. 

A link to a site with info on the book and a link to purchase the book: http://www.necsi.org/publications/businessdynamics.html.

http://www.amazon.com/exec/obidos/ISBN=007238915X/newenglandcompleA/102-6719924-9612113

From the preface: 
This book introduces you to system dynamics modeling for the analysis of policy and strategy, with a focus on business and public policy applications.  System dynamics is a perspective and set of conceptual tools that enable us to understand the structure and dynamics of complex systems. System dynamics is also a rigorous modeling method that enables us to build formal computer simulations of complex systems and use them to design more effective policies and organizations.  Together, these tools allow us to create management flight simulators-microworlds where space and time can be compressed and slowed so we can experience the long-term side effects of decisions, speed learning, develop our understanding of complex systems, and design structures and strategies for greater success. Visit his web site about the book. Visit his site at MIT