Review By: James T. Heires
08/26/2002This book presents a brief but ample description of Dr. Eli Goldratt’s Theory of Constraints (TOC) and how to apply it to real projects. The book is organized into four major sections, covering project management today, the critical chain, organizational competitiveness, and the theory of constraints in practice.

TOC was first published by Dr. Goldratt in 1986 (The Goal). TOC is centered upon the principle of undesirable effects, and attempts to minimize their underlying causes. It is a sort of root cause analysis for project managers.

Critical Chain, on the other hand, is a scheduling technique (an improvement on Critical Path) designed to take advantage of TOC to achieve schedules that achieve organizational goals. Critical Chain takes into account task dependencies, like Critical Path, but is ultimately concerned with key resource availability.

The concepts outlined in the book shift the management focus away from cost control to that of maximizing throughput. The author’s balance sheet example is a very effective illustration of the bottom-line value of this new way of thinking. According to the author, the world is divided into two philosophical camps: the cost world and the throughput world. When faced with improving the bottom line, the cost world directs its attention to cost control, whereas the throughput world attempts to increase throughput. The difference in approaches is dramatic.

This 284-page book is organized into twenty-five short chapters. Many chapters include figures and tables to help illustrate the concepts presented. The book contains a table of contents, a glossary, an index, three appendixes, and endnotes after each of the four major sections. Each chapter ends with key concepts and a few questions about the chapter (the answers are in the appendix).

The author has combined a nice overview of the theory of constraints with some practical advice on implementing this project management technique. The resulting work should be read by anyone wishing to implement critical chain scheduling. There were enough weaknesses in the book, however, to warrant a more careful editing cycle before the next printing. Some typographical errors, clumsy word choices (e.g., contrariwise), and problems with flow (e.g., section II to III seemed abrupt) lead me to believe that the book was rushed to press.

The book’s brief chapters make it readable in short segments. Several examples are used effectively throughout the book. Some of the examples build from one chapter to the next (my preference), but others alas, do not.

The book has section endnotes instead of footnotes on each page. This made referencing the endnotes difficult, causing me to search for, and flip forward to the endnotes each time I encountered a reference.

The body of the work reads well, outside of these minor issues. The author employs Dr. Goldratt’s Logic Tree diagrams to illustrate the thought process behind TOC. Specifically, these diagrams explain the cause-and-effect relationships present in a project (or organizational) environment. Central to the concept of TOC is a five-step improvement process:
1. Select/Identify the leverage points that limit throughput.
2. Exploit the leverage points using Critical Chain scheduling.
3. Subordinate everything else to these decisions.
4. Elevate leverage points by taking action or making targeted investments.
5. Evaluate whether improvements will enhance throughput.

The preface sets the expectation that readers will learn how to better estimate their next project. The remainder of the book, however, teaches how to manage projects. The estimation challenge is rarely mentioned in the remainder of the book.

In the end, however, this book is a valuable reference and learning instrument. Serious project managers would do well to buy and read this book.