Disney confirmed on Thursday 14 December that it is purchasing Rupert Murdoch’s 21st Century Fox group of companies, including the 20th Century Fox film studio, for a blockbusting $52.4 billion in stock.

The deal – which had been rumoured and then backtracked on several occasions for months up to its formal announcement – gives Disney control over a number of hot media brands, such as the X-Men and Avatar film franchises, and popular TV sitcom Modern Family.

Terms between the leaders of the two conglomerates at the heart of the gigantic M&A operation appear to be in excellent shape, with Disney chief Bob Iger saying: “We’re honoured and grateful that Rupert Murdoch has entrusted us with the future of businesses he spent a lifetime building, and we’re excited about this extraordinary opportunity to significantly increase our portfolio of well-loved franchises and branded content to greatly enhance our growing direct-to-consumer offerings.”

Murdoch added: “I’m convinced that this combination, under Bob Iger’s leadership, will be one of the greatest companies in the world. I’m grateful and encouraged that Bob has agreed to stay on [as Disney chairman and CEO until 2021], and is committed to succeeding with a combined team that is second to none.”

Clearly, Iger and Murdoch see each other as kindred spirits and have significant respect for each other’s leadership abilities. But M&A procedures can be enormously wrenching for either side of the bargain, and horror stories of failed partnerships are legend. What kind of qualities do leaders on either side of an M&A need in order to make the deal a success – particularly if they are planning to have joint ownership of the resulting, new entity?

The Institute of Leadership & Management's head of research, policy and standards Kate Cooper says: “Various studies have highlighted how generally unsuccessful mergers and acquisitions can be – such as a one from Harvard that reported the failure rate at something between 70% and 90%. Purely on that basis, this enormous Disney/Fox deal would appear to have the odds stacked against it straight away.”

Cooper explains: “The important thing to remember here is that you’re not just merging two boards. When considering how the process will work out at board level, of course you must take into account the power dynamics and issues such as duplication of roles. But they can all be anticipated and, to some extent, managed with some keen attention to detail. Who is going to stay, who is going to go, and how are you going to help the relevant people stay or go, are questions that can be plotted out almost like a cause-and-effect thought experiment as you hammer out the terms of the deal.

“It’s when you get further down the organisations that it starts to get more complex. If, for example, you are merging two customer-service teams, each with 100 people, then the kind of power dynamics you see at board level are still going on. The major difference is that typically, less attention to detail is devoted to seeing how the teams can be successfully drawn together, and deciding on how a successful outcome should look and feel. It’s a huge and unwieldy task.”

Cooper notes: “Among the many reasons cited for the failure of mergers, two of the most prominent are over-optimism about the returns, and not giving enough attention to what we might call post-merger ‘aftercare’ – in other words, examining how the merged sets of staff are taking to each other and adjusting to any changes that may have occurred in their working environments as a result of the process. One-way, top-down communication in the vein of, ‘We’re merging, and this is bound to be great for everyone concerned’ is meaningless, unless morale on both sides suggests that the two groups of workers are already enthused about the outcome.

“More often than not, though, you will need to put in significant effort to ensure that such enthusiasm is in place – and that’s a complicated and expensive task. Which is the main reason why the energy that drives mergers is all too often focused on the boards, and how their members will react on a personal level. Meanwhile, there are hundreds of other individuals who all have similar, personal concerns – but less powerful voices for articulating them. Not forgetting about those voices will increase your chances of success.”

For further thoughts on effective communication, check out these learning resources from the Institute

Image of Bob Iger (L) and Rupert Murdoch (R) courtesy of The Walt Disney Company