Nick Theakstone had better be up for a challenge. His anticipated promotion to the role of the chief executive of Group M UK will test his diplomatic skills to the utmost.
According to insiders, there are continuing "creative tensions" between Group M and its agencies within the WPP group - Mediaedge:cia, MediaCom and, last but by no means least, MindShare.
Last week's game of musical chairs is unlikely to resolve those tensions - in fact, according to some observers, they may just allow some of them to surface more overtly.
The reshuffle was triggered by the decision that the time was right for Alexander Schmidt-Vogel, the chairman and chief executive of MediaCom Worldwide, who recently celebrated his 59th birthday and who recently made a characteristically enigmatic contribution to the Venice Festival of Media, to embark upon a new phase of his career.
And, of course, the group had a ready-made replacement waiting in the wings. Steve Allan, the chief executive of Group M UK, was previously the UK chief executive of MediaCom - and during his five-year stint in that role, established it as the number-one UK media buying agency. Who better to take the global network to a new level?
On the other hand, there are those who wonder just how Allan was persuaded to accept. Those who know him say he loves life in London, doesn't much care for the non-stop travel that a global chief exec's life entails, was already massively well remunerated - and to cap it all, his new job is arguably a step backwards, in the short term anyway.
Because MediaCom's global network is patchy to say the least -the UK and Germany are arguably its only sizeable first-rate op-erations - and on a day-to-day basis, he'll be working almost in a vacuum, as the agency is barely on the radar in the US market. On the other hand, he is renowned for liking a challenge.
Whatever. His departure opens up a new role for Theakstone, 47, and a ticklish proposition it may turn out to be. Some have been moved to point out that, by background, Theakstone is a trader - and that Group M needs something far more sophisticated than a mere trader, given the speed at which it has been outgrowing its initial conception as a centralised media trading operation for the WPP family of agencies.
But that somewhat misses the mark. Yes, Theakstone was once MindShare's investment director, his remit expanding to embrace the same function at Group M when it became operational at the beginning of 2004. At that stage, it negotiated on behalf of just MindShare and Mediaedge:cia, which was then very much the junior partner.
However, when MediaCom billings were also added following its acquisition by WPP in 2005, and Group M was restructured accordingly, Theakstone became its chief operating officer, and took on a far broader range of roles under the unit's new boss, Allan.
This, though, takes us to the nub of the matter: the integration of MediaCom was said to be the source of festering discontent that persists to this day. Allan wasn't the only senior MediaCom executive to cross over - Mark Collins came in to head up the broadcast side, Steve Goodman was given responsibility for press trading and David Kyffin for direct response.
It was seen by some MindShare people as a wholesale takeover of their baby. MindShare has always regarded itself as the first among equals in the WPP family of media agencies. Group M was, after all, its creation, and was devised to do the dull and dirty work in the trading arena while MindShare got on with the infinitely cleverer job of building an exquisitely well-appointed House of Media.
In the past couple of years, under the direction of Irwin Gottlieb, the global chief executive of Group M, the balance of power has shifted inexorably. Group M is now where the group's media vision is being developed. It takes the initiative in areas such as advertiser-funded content, for instance, and develops the most radical forward-thinking ideas about how the whole media marketplace should evolve.
Witness the Business Week think-piece by Gottlieb back in February that provoked so much debate in the US. In each local market, WPP agencies have been invited to defer to Group M, rather than their own network structures, on more and more issues.
Some feel that this undermines the unique selling proposition of the individual networks - and they've been exploring ways to reassert their sovereignty. However, Jed Glanvill, Tom George and Nick Lawson, the UK chief executives of MindShare, MediaCom and Mediaedge:cia respectively, had a respect for Allan bordering on fear. They may have no such deeply held feelings where Theakstone is concerned.
There are, of course, clear profit and loss responsibilities, and some lines of command on WPP's corporate organogram are unambiguously charted in heavy black lines. It's also true that the chief executive of WPP, Sir Martin Sorrell, has no aversion to knocking heads together when the occasion demands.
But, as in any large and complex community of commonly owned companies, there are grey areas too - and it's these grey areas that will test Theakstone's mettle over coming months.
Is he up to the task? It's a question we would have loved to have put to the man himself, but, last week, as the news of his elevation began to leak out, Group M went into panic mode and a lock-down was declared.
But one former colleague, Chris Locke, the group trading director at Starcom MediaVest Group, reckons Theakstone's eminently well-qualified. Locke says: "He's always been very astute politically. There are always tensions in every family and you pick your friends, don't you?
"It's true that he's grown up with the likes of Jed and Tom and Nick and they see him more as an equal. But it's no surprise - and if they'd brought someone in from outside, there'd be a far higher risk of a meltdown. And, after all, he's bald, which is always a good start if you want to get on at Group M."