Editor's Note: McKinsey's One Degree of Separation

You may be one of the consultants whose books sits in a stack here in our office. Following the arrival of each text, we frequently will receive a call from a publicist — to whom we offer a standard apology and some time-tested reasoning as to why we choose not to review books. So, using this page to endorse any one book could send a mixed message.
Nonetheless, allow us to say that there's one book that deserves to be near the top of every consultant's pile: Lou Gerstner's memoir about his years at IBM, Who Says Elephants Can't Dance? Some of you may rightfully disagree. First, you'd probably tell us that Gerstner was not a consultant when he wrote it, nor is he one today. Second, you'd probably tell us that Gerstner's book is already three years old.
If it were not for the hopeful notion that this column and our cover story could together pay some synergistic dividends, we'd have to concede to you on the second point. Not on the first, though. You see, Lou Gerstner has always been a consultant. And despite having served as IBM's chairman and CEO for nine years and performed leadership tours of duty at RJR Nabisco, American Express, and, more recently, The Carlyle Group, Gerstner's professional DNA routinely exposes his true identity. "I now realize that I was always — even to the end — an outsider," he writes.
For a leader this is a surprise confession, intended not to garner sympathy but perhaps to reveal the disposition required of executives who are tasked with bringing vast change to an organization. It's clear that Gerstner's detachment or independent-mindedness made his approach mirror that of a consultant. Some could argue that such qualities were largely inbred, given the fact Gerstner spent more years at McKinsey & Company (1965–78) than anywhere else during the span of his career. Gerstner's independence aside, Elephants should remain a classic consulting text because of its determined focus on what is generally accepted to be the weak knees of the consulting profession — the hinge where strategy and execution meet.
The book relates a number of carefully chosen anecdotes, including one that details a brief encounter with a 79-year-old Thomas Watson, Jr. — the man who brought IBM into the computing age. Watson urges IBM's new leader to shake it up "from top to bottom." At the conclusion of Elephants, you can imagine that there have been just three IBM CEOs who have ever really mattered: Watson, Gerstner, Palmisano.
This book may have even deeper meaning for the consulting world when you consider that Gerstner personally knew and admired McKinsey's modern founder, Marvin Bower. It was Bower, Gerstner has stated, who taught him the importance of leading with principles. In the end, when Gerstner passes the baton to Palmisano, those familiar with IBM's maturing consulting ambitions may wonder from whose hand Gerstner himself received it.