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Avoiding the “Synergy Trap”: Practical Guidance on M&A Decisions for CEOs and Boards


  • Mark L. Sirower,

    1. Advises senior management teams and boards on strategic M&A decisions and is a visiting professor at New York University's Stern School of Business. He is author of The Synergy Trap: How Companies Lose the Acquisition Game (Free Press, 1997, 2000), and previously led the M&A practice at The Boston Consulting Group in New York.
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  • Sumit Sahni

    1. Vice President and Director of The Boston Consulting Group in New York and a leader of its Global Strategy Practice.
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When a major acquisition is announced, investors try to understand where the value is going to come from and whether the acquirer has a plan to achieve that value. Deals are often brought to market with one big synergy number and a statement that the deal will be “accretive” to earnings. The problem, however, is that investors can't understand or track one number. Going to market with just one number also suggests that the acquirer has no credible plan, which in turn gives investors more reason to sell shares than to buy, particularly when a significant premium is being offered.

According to academic studies, the acquiring company's stock price has fallen upon the announcement of more than half of the large corporate M&A deals that have been transacted since the early 1980s. And as the authors find in their recent study of the merger boom of 1995–2001, such negative stock price reactions are a fairly reliable predictor of future disappointing operating performance and, in many cases, further stock-market underperformance.

But as the authors also point out, such studies focus mainly on average results. And whether or not mergers pay on average doesn't really matter-at least not to well-informed executives and boards. What matters is that the executives who make these major capital investment decisions, and the boards that monitor them, have the tools that can help them distinguish the good deals from the bad before committing shareholder capital.

For any proposed transaction requiring a significant premium over market, the authors present a simple, earnings-based model for the target that yields combinations of cost reductions and revenue enhancements that would j ustify that premium. The authors go on to present a capabilities/market access matrix that can be used to assess the potential sources of synergies in any deal. Their methodology can be used to inform and guide detailed discussions about the combination of revenue and cost synergies that management believes it can achieve in a potential deal, and that should become the main focus of management's communication to investors.

While no substitute for a carefully considered DCF valuation, the authors' method is a complement to DCF and effectively translates DCF merger criteria into the operational language that is familiar to most corporate managers and investors. In so doing, it can help boards avoid obvious mistakes of overpayment, particularly when “accretive” deals clearly fall short on economic grounds.