How to turn your post-merger integration into a success: 5 best practices

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Key findings from Eight Advisory’s post-merger integration survey.

In the fast-paced world of mergers and acquisitions (M&A), closing the deal is merely the first step. When integration is a key part of the strategy, the true challenge – and the greatest opportunity – lies in successfully blending the acquired business to unlock its full potential.

While M&A is often aligned with broader corporate goals, many deals fail to meet their initial expectations due to flawed integration processes. So, how can businesses ensure successful post-merger integrations (PMI)?

Eight Advisory’s key insights on PMI success
Eight Advisory, a trusted partner for integration programs across Europe, recently conducted a comprehensive survey of 91 companies worldwide to uncover what really drives success in PMI. Their findings offer actionable strategies that M&A professionals can adopt to navigate the complexities of integration.

Why do many integrations fail?
While a weak M&A thesis or strategy may contribute to failure, Eight Advisory’s research highlights a more pervasive culprit: poor integration execution. Cultural misalignment, lack of synergy realization, and insufficient preparation often derail even the most promising deals. These blind spots can erode value, causing frustration for management and investors alike.

In the tables below you find the challenges that are the most underestimated in the integration process.

What sets successful integrations apart?
The survey identified several critical factors that separate successful integrations from those that fall short:

Strong process and governance: Establishing a structured integration framework is vital. This includes ensuring continuity between pre-deal and post-deal activities through meticulous due diligence and seamless transition planning.

Cultural integration and talent retention: Misjudging cultural differences or failing to engage key personnel can hinder collaboration and efficiency. Addressing these early in the integration process fosters smoother transitions and prevents attrition.

Synergy realization: Companies often struggle to fully achieve the synergies outlined during the deal phase. Successful integrations track these synergies rigorously, balancing ambition with practicality.

Adaptable operating models: Tailoring the integration approach – whether full alignment or selective autonomy – to the specifics of the deal and company culture is essential for preserving business continuity and unlocking efficiencies.

Leadership and ownership: Appointing a dedicated integration leader ensures accountability and accelerates decision-making, preventing delays and roadblocks.

In the table below, you find the most important success factors for integration, according to the PMI research by Eight Advisory:

5 Best practices for post-merger integration
Based on Eight Advisory’s findings, here are five of the best practices M&A professionals should prioritize:

1. Conduct thorough due diligence
Pre-deal due diligence is not just about financial and tax assessments – it must also include detailed evaluations of operational, technological, and organizational aspects. Inadequate pre-deal analysis often leads to post-deal challenges like business continuity issues or overlooked costs.

Why it matters: Provides clarity on the target’s operations, helping to avoid surprises post-acquisition. Enables better synergy analysis, a critical factor for financial success.

Tip: Perform an initial synergy assessment during due diligence and validate it post-closing to ensure realistic financial and operational planning.

2. Engage operational experts early
Involving operational teams early ensures that those who will execute the integration are part of the planning process. These experts bring valuable insights into the target's processes and help identify realistic synergies and potential challenges.

Why it matters: Early involvement fosters ownership, improving commitment and execution. Enhances accuracy in assessing operational and synergy assumptions.

Tip: Expand the circle of involved experts gradually to maintain confidentiality while benefiting from their specialized knowledge.

3. Track synergies in detail
Synergies, whether cost-saving or revenue-generating, don’t materialize on their own. Detailed tracking mechanisms are essential to measure, monitor, and achieve the identified synergies.

Why it matters: Synergies often account for a significant portion of a deal’s value. Robust tracking boosts success rates. Companies with detailed tracking achieve 90 percent of their synergy targets, compared to just 71 percent for high-level tracking.

Tip: Integrate operational and financial KPIs into existing management routines to quickly identify and address underperforming areas.

4. Define a target operating model
A clear operating model balances integration efficiency with business continuity. Over-integration can stifle innovation, while under-integration may fail to realize synergies. Tailor the model to the acquisition’s objectives and organizational cultures.

Why it matters: Provides clarity and direction for teams, reducing uncertainty. Accelerates the transition to a stable and effective operating state.

Tip: While back-office functions often benefit from full integration, core operating teams may require tailored approaches to minimize disruption.

5. Appoint a dedicated integration leader
A dedicated integration leader ensures cohesive execution of the integration process across various workstreams. This role accelerates decision-making, resolves bottlenecks, and maintains focus on achieving strategic objectives.

Why it matters: Increases integration success rates: 75 percent for deals with a leader versus 64 percent without. Provides centralized oversight and accountability for integration progress.

Tip: Assign a leader who can focus exclusively on the integration to maximize efficiency and results.

A call to action for M&A professionals
Post-merger integration is not merely an operational exercise – it’s a strategic necessity. The Eight Advisory survey shows that even seasoned acquirers can overlook critical elements, underscoring the need for robust preparation and execution. By embedding the practices outlined above, M&A professionals can increase their chances of turning bold acquisitions into enduring successes.

You can download the PMI-research by Eight Advisory here

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