When it comes to acquisitions, some Asian companies are forging a novel path through the thicket of postmerger integration: they aren’t doing it. Among Western companies, the process can vary considerably from deal to deal, yet it’s an article of faith that acquirers must integrate quickly. Otherwise, the logic goes, they may lose the momentum of a deal before they can capture the synergies that justified it.

But in Asia, a sizable proportion of acquiring companies aren’t rushing to become hands-on managers. With over 1,900 deals, valued at $145 billion, in 2009 alone, the trend is worth noting.¹ In a recent review,² we estimated that roughly half of all Asian deals deviated significantly from the traditional postmerger-management model, which aims for rapid integration and the maximum capture of synergies. Over a third of the Asian deals involved only limited functional integration and focused instead on the capture of synergies in areas such as procurement, with an overwhelming emphasis on business stability. An additional 10 percent attempted no functional integration whatsoever.

By the standards of developed markets, at least, this approach is counterintuitive. When potential synergies aren’t captured in an initial postmerger shake-up, they become all the more elusive...