Three out of four mergers are either disappointing or outright failures, and "people problems" are cited as the top integration failure factor.
The figures come from the human resource specialists Watson Wyatt.
Its strategic rewards consultant, Mr Roger Dolphin, explained: "Experience shows that people issues are consistently the most difficult to resolve and the reason why the majority of deals under perform.
"The ostrich approach to human capital during any integration is disastrous.
"However, a pre-meditated, well-managed integration strategy, often driven by human resources, can result in significant returns in terms of faster integration, lower deal costs and greater productivity."
Traditionally, the legal, financial and operational aspects of M&A deals have received the greatest attention, but executives who have been through the merger process are recognising that managing the human side of change is critical to maximising deal value.
Mr Dolphin pointed out: "As the attitude of the workforce can have a major impact on …