The First Ninety Days After a Merger: What Retained Leadership Should Focus On

The day a merger closes is not the end of the work — it is the beginning of a period that determines whether the transaction delivers its intended value. For retained leadership teams, the first ninety days are characterised by simultaneous demands: reassuring staff, meeting new reporting requirements, maintaining customer service, and making integration decisions under time pressure.

Days 1–7: Communication and stability

The immediate priority is controlled communication. Staff, customers, and suppliers will hear about the merger through various channels — some accurate, some not. A day-one announcement, delivered by the retained leadership team (not the acquirer’s corporate communications department), sets the tone.

Key actions:

• Hold an all-staff briefing on day one, with time for questions
• Send a direct communication to your top twenty customers within 48 hours
• Confirm to key suppliers that existing terms and contacts remain in place unless otherwise agreed
• Identify the three most anxious members of your team and speak with them individually within the first week

Resist the urge to make operational changes in the first week. Stability signals confidence.

Days 8–30: Integration planning

By the end of the first month, the retained leadership team should have a written integration plan covering:

• Reporting: What new reports are required, to whom, and by when
• Systems: Which systems will change, on what timeline, and who is responsible for migration
• Roles: Any changes to reporting lines, job titles, or responsibilities — communicated clearly to affected staff
• Culture: Explicit discussion of what will change and what will be preserved in the combined operation

This plan does not need to be exhaustive. It needs to exist, be shared with the retained team, and be reviewed at the 30-day checkpoint.

Days 31–60: Execution and adjustment

The second month is when integration decisions meet operational reality. Systems migrations encounter problems. Staff who were reassured in week one begin to see changes that concern them. Customer enquiries about “what the merger means for us” increase.

Common pitfalls at this stage:

• Agreeing to integration timelines set by the acquirer without assessing local capacity to deliver
• Failing to escalate staff concerns until they become resignations
• Neglecting existing customer relationships while focusing on internal integration tasks
• Making reactive decisions under pressure rather than referring back to the integration plan

Weekly leadership team meetings during this period should include a standing agenda item: “What integration decisions did we face this week, and did we have adequate information to make them?”

Days 61–90: Checkpoint and forward planning

The 90-day checkpoint is not a celebration — it is an honest assessment. Questions to address:

• Are customer service levels maintained compared to pre-merger?
• Have any key staff departed? If so, what was the cause and what is the mitigation?
• Is the retained leadership team reporting structure functioning?
• What integration tasks remain incomplete, and what is the realistic timeline?
• Does the retained leadership team have the authority and resources it needs for the next quarter?

Document the answers. This summary becomes the basis for your ongoing relationship with the acquirer’s management and for any extension of transition advisory support.

When external advisory support helps

Not every merger requires external transition support. It is most valuable when:

• The retained leadership team has no prior integration experience
• The acquirer is significantly larger and operates at a different pace
• Staff anxiety is high and the leadership team lacks bandwidth for both integration and daily operations
• The acquirer’s integration team is centralised and does not understand local operations

The cost of reactive decision-making during the first ninety days — lost staff, damaged customer relationships, delayed integration — routinely exceeds the cost of structured advisory support during the same period.