Most synergy slippage is not announced. It accumulates in the first hundred days, quietly, while everyone is congratulating themselves on a clean close.
Disciplined post-merger integration is the single highest-leverage capability in mid-market private equity right now — and the playbook for it is not what it was five years ago.
Five years ago the integration discipline was dominated by carve-outs from large corporates. Today the volume sits in platform-and-bolt-on structures, often three or four acquisitions inside two years, with no two integrations the same. Sequencing has become a strategic question in its own right.
At the same time, the talent profile has changed. Functional leaders at sub-€100m EBITDA companies are sharper than the legacy playbook assumed. Treating them as targets for replacement rather than partners for redesign is now the most reliable way to destroy value.
The first is the day-one operating model — not the org chart, but the decision rights, escalation paths, and management cadence. Most plans confuse the second for the first. The second is the commercial integration: customer ownership, pricing alignment, and cross-sell governance. This is where the upside lives, and where most sponsors under-resource.
The third is the systems and data work, which is unromantic and always longer than the plan assumes. Underwriting a six-month systems migration and getting eleven is one of the most common silent value leaks in mid-market PE.
The integration management office is almost always under-staffed. The instinct is to staff it from existing management; the result is that the existing management does two jobs badly. Interim operators — senior, sector-fluent, and explicitly there to leave — solve this and protect the operating business at the same time.
Sponsors who run a real IMO and resource it with the right mix of internal leadership and external interims tend to deliver synergy targets on schedule. Sponsors who run a slide deck with 'IMO' on it usually do not.
This is the kind of problem we work on. If you are leading a recent acquisition where the underwritten synergy is not yet visible in the operating numbers, the team at Grant & Graham would be pleased to talk. We provide integration management, interim leadership, and operating-model redesign to private equity sponsors and operating partners across EMEA. Contact us.