Beyond the Core: Expand Your Market Without Abandoning Your Roots.

• Author: Marshall, Jeffrey
• Position: BookShelf - Book Review

Beyond the Core: Expand Your Market Without Abandoning Your Roots. By Chris Zook. Harvard Business School Press, 215 pages. $29.95.

The critical concept in this well-conceived and generally lucid book is "adjacency." As detailed by Zook, a director of famed consultancy Bain & Co., adjacency essentially means expanding into related businesses, sometimes moving into a further one by using a first satellite as a springboard.

To wit: After American Airlines spun off its reservation system, creating Sabre--a business worth more these days than the troubled airline itself. Sabre later created its own adjacent business, the Web travel site Travelocity. In a related fashion, Nike Inc. moved aggressively from its core running shoe business into sports like basketball and golf.

Beyond the Core is the result of a comprehensive global study of such moves involving more than 180 companies, and includes short interview segments with 25 CEOs of the top growth performers, as well as an analysis of myriad adjacency moves in a range of industries than worked or failed. Zook argues that those with the best growth...