1. Develop a personal strategy

Whether you're on the acquisitive or buyout side, the upheaval of an M&A is a good time to reassess your own career. Often the senior team moves on, creating vacancies higher up, according to Mike Owtram, a partner at Kiddy & Partners, a business psychology firm. “There are opportunities to get involved in more aspects of the business or take more responsibility than in the past,” he said.

2. Beware culture clash

Creating a corporate identity is very difficult, Mr Owtram said. “For years people talk about themselves as a ‘company X' person.”

Duncan Angwin, Associate Professor of Strategic Management at Warwick Business School, advocates undertaking a cultural assessment of both companies, looking at everything from how decisions are made to how they compete.

Consider how much of the company's value is tied to culture, Elisa Hukins, global leader in cultural integration for Mercer's M&A team, said. “If you are buying a competitor to grow the brand, then you want to bring them inside your way of doing things. But if it is a complementary business and their culture adds to what they do, you are likely to destroy the value.”

3. Understand the new business

While due diligence is a standard procedure, most companies fail to do an audit after the transaction has gone through. “What have you actually bought? There are always skeletons,” Professor Angwin said.

“A danger with deals going through so quickly is that people are saying

‘we'll bring them together then figure it out later'. It's going to have long-term effects on the value of the organisation,” Ms Hukins said.

4. Identify key people

“Failing to retain and reward the right people is a key reason why mergers fail,” Nick Collett, a senior lecturer on financial management at Manchester Business School, said. The right people may not be the most senior. Mr Owtram said: “It might be someone who knows the computer systems, has technical expertise or knowledge of customers.”

According to Dr Collett: “Don't presume that your team are the correct people to run the new business. Hold interview panels chaired by an external consultant.”

5. Merge where necessary

Removing all trace of a company can result in identity loss, Ms Hukins said. With HSBC's takeover of Midland Bank in 1992, it made sense to leave the brand untouched. “Customers weren't confused and staff didn't realise they'd been taken over,” Professor Angwin said. Integrating systems, such as customer databases or staff payrolls, however, may be critical.

6. Act at the right speed

The common philosophy is to look for early wins to report back to shareholders, Dr Collett said. Mr Owtram added: “There's a case for doing what you're going to do quickly and then giving people time to adjust.”

Most companies underestimate the time and challenges involved integrating businesses, Professor Angwin said.

7. Don't be inward looking

A common fault is to focus on how the merger is playing out internally and neglect the customer. But you've got to remember you have competition. “Keep your eye on the commercial football,” Professor Angwin said. “It's a good time for a product launch or advertising campaign.”

8. Communicate effectively

Mr Owtram: “People appreciate clarity - if you can't give them a decision, then tell them what the process is.” Use senior leaders to spell out change as well as engaging with people on a one-to-one basis. And beware of “conquering heroes syndrome”, the attitude “we bought you so we know best”, Professor Angwin said. “You immediately get people's backs up.”

9. Integrate strategically

Many employees will be reassessing their own careers. Where redundancies are necessary, ask them to stay on to help with the integration, Professor Angwin said. “The employees who remain are very aware of the way you acted.” The cost of integration needs to be factored in from the start. Ms Hukins said: “We often hear people say: ‘We spent all the money on the deal, we don't have any more to spend on getting people aligned.' That gets alarm bells ringing.”

10. State the positives

“Focus on the ways in which the new situation can benefit the existing business,” Dr Collett said. Very few companies realise that those in the business they are buying may welcome a new owner. “They might have been starved of funds. If morale is weak, demonstrate you are coming with help, not a hatchet.”

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