The announcement goes out the same day in both countries. Shareholders briefed, leadership teams introduced, synergies quantified in the press release. Eighteen months later, the real integration is still stuck: two cultures that don’t talk to each other, systems that were never unified, and a local team reading every decision from headquarters as an imposition. From day one, nobody on the deal held the exclusive mandate to make the integration actually work.
That’s what almost always fails in a cross-border merger or acquisition. Not the financial side, and not the legal side, those are usually handled well. In an Accenture survey of more than 400 executives across Europe and the United States, more than 7 in 10 admitted these deals are more complex than domestic ones, and only 30% achieved a genuinely satisfactory operational integration. What fails is the daily execution of the integration: work that doesn’t fit inside the local leadership team, because they still have a business to run, and doesn’t fit inside the parent company’s team either, because they’re thousands of kilometers away without local context.
Cross-border deals have historically failed at rates of up to 70%, well above domestic deals, and almost always because of what happens after signing, not because of the deal itself. When a company buys or merges with another abroad, the first weeks go entirely into closing the deal: due diligence, negotiation, communication. The following months should go into integration, but there’s almost never one person with clear authority and full-time dedication to it.
Local executives keep running their usual operating agenda. Headquarters executives run the integration from a distance, never on the ground. The result is a process that drifts forward on inertia, with nobody making the hard calls (merging teams, closing duplications, forcing one system over another) because those calls create friction, and no one local wants to be the one who triggers it.
An interim manager steps in to fill exactly that gap, not a senior consultant brought in to diagnose and hand over a report. They have no ties to either team, no career inside the resulting company to manage, and an explicit mandate: execute the integration, not survive it politically. That frees them to make decisions a local or headquarters executive would avoid, given the personal cost of making them.
This matters even more when the deal crosses a border, because on top of the normal resistance to any integration there’s physical distance, unfamiliarity with the local market, and often a different corporate culture on each side of the deal, the kind of friction covered in more depth in International mobility: the cultural challenge that no one addresses. An interim manager who has already run similar processes knows the typical friction points before they surface, and acts on them instead of reacting once they’ve already stalled the operation.
Bringing in an interim manager with an integration mandate from the moment the deal closes, not months later once friction has already built up, changes the outcome in measurable ways. It’s part of a broader shift already visible in how interim management is maturing in Spain: companies increasingly treat it as a planned tool, not a last resort. Consolidation decisions get made in weeks, not quarters. Local teams have a single point of contact instead of contradictory instructions arriving from headquarters. And the acquiring company avoids the most expensive scenario of all: paying for a deal that never delivers the value it paid for, because the integration quietly dissolved with nobody accountable for it.
Closing an interim management mandate well often decides whether it actually worked. In a cross-border integration, that well-executed close is the difference between a deal that works on paper and one that works on the P&L.
Companies that manage their international deals well don’t have less friction than everyone else. They have someone, from day one, whose only job is to resolve it.