Driving Post-Merger Integration success

Driving PMI success: The five Pillars and Enablers you can’t ignore

Between 70% and 90% of mergers and acquisitions fall short of their intended value, often due to the challenges of Post-Merger Integration (PMI). No matter the size of the deal, PMI is a high-stakes endeavor. While every integration has its nuances, the core principles of effective execution remain the same. Whether you’re bringing together a team of 50 or a global organization of 5,000, success depends on getting the fundamentals right.

In this article, we offer a practical framework for executing an integration well to achieve pre-identified synergies and deal value. We focus on the structures, behaviors and decisions that enable a high-performing PMI process, one that clears the path for synergy capture, organizational alignment and long-term value creation.

Pillar 1 for PMI: Focused and empowered leadership

Executing a successful integration requires the right leadership structure. You should appoint an Integration Leader who must be fully dedicated, empowered and accountable for driving execution. When leadership is a part time responsibility, without authority or executive backing, decisions stall, execution slows down, and value realization is put at risk.

• Integration must have a dedicated and capable leader. The Integration Leader must be fully focused, have direct access to the executive leadership and the authority to make decisions. They should be well respected across the organization; be capable of operating cross-functionally, of anticipating interdependencies, and be able to actively pull teams out of silos to ensure coordinated decision-making across functions and geographies.
• Leadership must focus on and be accountable for value realization. It’s not enough to get through Day 1; the leadership team must be held accountable and focused on delivering the synergy targets and goals outlined in the investment case.
• Executive sponsorship is non-negotiable. When the CEO or senior leadership is misaligned or fails to show commitment to the integration or its objectives, it creates confusion below. Teams lose direction, and resistance builds. A compelling mandate from the top provides clarity and drive for the integration process.

Pillar 2 for PMI: Cross functional thinking

Too often, integration is approached as a checklist of activities by individual functions. Integration typically involves cross-organizational transformation. When siloed thinking drives the integration process, it can lead to delayed synergies and erosion of the deal value.

• A cross-functional execution plan is essential. The integration plan must be defined as a set of distinct, well-defined deliverables, owned and executed through cross-sectional collaboration. These deliverables should be easy to understand and align with the overall strategic goals of the integration effort. A cross functional working group should be established early to provide a forum to identify interdependencies, align timelines, establish clear escalation paths and create space for collaborative problem-solving.
• Interdependencies must be actively managed. Changes in one function can create a downstream impact for others. For example, if the Sales team decides to expand into a new region, it must coordinate with the regulatory and legal teams to meet compliance requirements and avoid costly delays. Function Leaders need to identify where and how they might need support from other parts of the organization to achieve their goals. This is especially important in global integrations where interdependencies can be more complex and failure to coordinate carries greater operational risks.

Pillar 3 for PMI: Shared vision and culture alignment

It is very rare that the organizations you are integrating have the exact same cultures. Culture clashes, whether unspoken or overt, are among the top reasons why integrations fail. Cultural alignment is not about choosing one organization’s culture over the other, rather it is about defining clearly what the new organization is going to be.

• Cultural Differences must be identified and addressed early. Cultural differences between organizations show up in different ways. This can range from how decisions are made, how processes are managed or how money is spent. Maybe one company prides itself on informality while the other is methodological and process driven.  Neither is wrong, but left unacknowledged, these differences can stifle integration, slow down operations and erode potential synergies. When envisioning the future organization, both sides need to feel “heard”. Unspoken beliefs about “how things work” can quietly derail trust, productivity, and morale, demotivating transferring employees. Thus, it is important to bring them to the surface and address them explicitly.
• The target culture must be clearly defined and communicated. Once differences have been identified, leadership must provide clarity across the organization on which aspects of the various cultures will remain, what will evolve and the rationale behind any changes. This is important for all employees to understand; those who are part of the buying organization and selling organizations irrespective of the deal size.
• Thoughtful onboarding accelerates belonging. Effective onboarding requires early, detailed planning to ensure a smooth transition for transferring employees. Leadership must clearly communicate any changes to roles, reporting lines, ways of working, and benefits. Robust onboarding plans should also include a detailed IT readiness plan to ensure full access to systems, workspace, and tools from Day 1, a comprehensive benefits transition plan outlining any changes and their implications and a hyper care support team in place to address any operational, HR, and IT issues during the critical first weeks of integration.
• Cultural Integration requires dedicated funding. Cultural integration is a critical operational priority that requires upfront and ongoing investment to ensure alignment, engagement, and sustained momentum thought integration. Funding should cover leadership workshops and employee training sessions to reinforce shared values and ways of working. It should also support the Day 1 celebrations events, branded swag and communication and marketing efforts to boost morale and generate excitement and a sense of belonging. In addition, funding should also cover culture pulse surveys to monitor progress and proactively address emerging issues.

Pillar 4 for PMI: Functional roadmaps

The execution of a successful integration requires detailed functional roadmaps that translate strategy and vision into clear accountable actions.

• Functional roadmaps must define objectives, timelines, and dependencies. Every function must understand clearly the goal of the integration and the risks if deadlines are missed. Roadmaps should break down work into clear deliverables with assigned accountability. These roadmaps should cover Day 1 priorities including ensuring continuity of payroll, systems access, customer support etc. and Day 100 priorities that create early momentum and signal integration progress.
• The deal structure will have an impact on the integration design. Integration plans will differ depending on whether the transaction is structured as a stock deal versus an asset deal. A stock deal might allow for a smoother Day 1 transition while an asset deal might require more lift upfront. Integration plans need to be tailored to these legal and operational realities.
• Joint planning will enable success and cover blind spots. Planning should involve teams from the buying and selling organizations. Early collaboration helps surface assumptions, build trust and ensures that the plan reflects the realities of both businesses and people.
• Roadmaps must extend beyond Day 100 to drive full value capture. While Day 1 and Day 100 milestones provide critical early focus, full integration often requires 18 – 24 months to harmonize processes, stabilize systems and unify culture. Integration discipline should be maintained well beyond the initial milestones to ensure long-term success.

Pillar 5 for PMI: Strategic communication and engagement

Communication is one of the most critical drivers of success. It must serve both internal and external audiences; ensuring that employees remain aligned while external stakeholders remain confident in the business as the integration unfolds. Clear, transparent communication protects trust, maintains stability, and prevents uncertainty from slowing execution.

• Messaging must start from the top and cascade consistently. The CEO and senior leaders must champion communication efforts to set the tone and provide clarity on direction, decisions, and expectations. Consistent, timely, and visible leadership communication signals that integration is not just another initiative but a top priority.
• External Stakeholders require clear messaging transitions. Customers, Suppliers, regulators and investors are watching just as closely as employees. They need reassurance that operations will continue smoothly, relationships will be respected, and the direction of the business will remain sound. Some customers will leave at the first sign of disruption or confusion, making external messaging just as critical, if not more important, as the internal communication plan.
• Two-way communication channels must be established. Listening is just as important as messaging. Feedback loops like town halls and surveys allow leadership to hear concerns early, address misinformation and keep teams engaged. Externally, proactive engagement with customers and suppliers helps to surface emerging concerns and integration missteps before they happen

Execution Enablers for PMI

Tools and templates

Integration can easily become an overwhelming process without clear structures. Standardized tools such as reporting templates, trackers and decision logs help to reduce confusion and drive alignment across teams by creating a shared structure. Without structure, people spend more time figuring out how to work than doing the actual work. The right tools will help teams stay aligned move faster and avoid rework.  While creating the right tools is essential, the key is simplicity. Good tools are:

• Easy to access and easy to use
• Focus on the decisions they are meant to support. They are clear on the essential inputs and strip out anything that does not drive the decision-making process
• Reinforce consistent thinking around key issues like risks, metrics, milestones

Teams must avoid the trap of creating too many templates. A proliferation of templates creates confusion, not clarity. If a tool does not clarify or accelerate a process, then it is likely unnecessary.

Change Management capability

Successful integration requires intentional support for change in behavior. Even with a strong strategy, integration can stall when people do not understand what is changing and why it is changing. Change management provides the structure and framework to move people from awareness to adoption. It helps leaders assess change readiness, synchronize efforts across functions and tailor messages to what matters most to individuals. Done well, change management ensures that the business doesn’t just drive the integration, but it absorbs and sustains it.

Dedicated time and resources

Integration must be resourced like any strategic project. Beyond the appointment of an integration leader, organizations must set aside time, talent and funding to execute effectively. This will mean assigning dedicated project managers and functional leads with the bandwidth to focus on integration priorities.  Expecting people to run full speed with integration while also juggling their day-to-day jobs will lead to delays and value destruction.

Adequate funding should be allocated early not just for travel but for critical activities like onboarding, technology harmonization and external advisory support.

Like any large project, integration requires structure; clear roles and responsibilities assigned across board, a master project plan and tools to track decisions and dependencies.

Foundational Enablers for PMI

Access to timely data

Integration Leaders need timely and transparent data to drive decisions and manage risk. This begins pre-close where early access enables teams to size synergies, assess risks, design workstreams and create functional plans with confidence. Without the right data, teams are forced to make assumptions which may be incorrect, increasing the risk of overestimating potential synergies, and of overlooking risks and creating executional delays. While some data may be restricted pre-close due to antitrust or competition concerns (e.g. pricing, competitive information), critical and operational and relevant financial data should be shared to accelerate readiness. Equally important, teams need visibility into real-time data to track progress, spot issues, and plan ahead.

Technology: The critical cross cutting Enabler

Integration success depends on having the right digital infrastructure in place. Technology is often the longest, most expensive and most complex part of integration, yet it is frequently underestimated. The right technology supports seamless data access, workflow automation and collaboration across times zones and functions.

Technology transitions must be thoughtfully managed to avoid conflicts between legacy systems and new platforms. Poor planning leads to fragmented systems, redundant tools, and a frustrating experience for users across the organization. Proper planning for technology changes, especially data transfer and integration, is critical to protect business continuity and avoid costly disruptions. When teams take shortcuts and implement temporary technology fixes, they often create hidden costs and future problems that slow down integration.

Early decisions about which systems to keep, merge or sunset are critical to maintain operational continuity and avoid chaos during the immediate post Day 1 phase.

About the author

Ezinne Eze-Ajoku is a physician and project manager dedicated to helping healthcare and life sciences organizations navigate complex change. With extensive experience in both the public and private sectors, she has worked across multiple industries, leveraging her expertise to drive strategic initiatives, streamline operations, and enhance stakeholder collaboration. Passionate about transformation and organizational excellence, she helps teams align on mission-critical goals and deliver sustainable impact in an evolving healthcare landscape. Ezinne also holds a Doctorate in Public Health Management and Leadership from Johns Hopkins University and a Master’s in Public Health from Harvard University.

Lawrence Conway is a transformation and integration expert with 25+ years of experience across consulting and industry. A former a-connect Independent Consultant and now client, he has led large-scale M&A, ERP, and cost optimization programs in CDMO, Medical Device and manufacturing environments. Lawrence combines strategic insight with hands-on execution to deliver results in complex, high-stakes settings.