---
name: planning-post-merger-integration
language: en
description: Structures Day 1 readiness, 100-day plans, and long-term integration workstreams with synergy realization tracking. Use when planning PMI, building integration timelines, or tracking workstream execution.
tags:
  - planning
  - mergers-and-acquisitions
metadata:
  author: casemark
  practice_areas:
    - M&A Advisory
    - Corporate Development
    - Investment Banking
  document_types:
    - Plan Document
  skill_modes:
    - Planning
---
# Planning Post Merger Integration

Structures Day 1 readiness, 100-day plans, and long-term integration workstreams with synergy realization tracking.

## When To Use

- Building a Day 1 readiness checklist after signing or regulatory clearance
- Developing a 100-day integration plan with phased milestones
- Standing up functional workstreams (Finance, IT, HR, Operations, Commercial, Legal) with owners and deliverables
- Creating a synergy realization tracker tied to deal-model assumptions
- Preparing Integration Management Office (IMO) governance frameworks
- Assessing cultural integration risks and designing mitigation plans

## Inputs To Gather

- **Deal rationale and synergy thesis** — revenue synergies, cost synergies, and strategic rationale from the investment memo or board deck
- **Target company org chart and headcount** — functional leadership, reporting lines, key talent identified during diligence
- **Synergy model** — line-item cost savings and revenue uplift with timing assumptions (Year 1, Year 2, run-rate)
- **Due diligence findings** — red flags, IT system landscape, contract change-of-control provisions, pending litigation, regulatory conditions
- **Transaction timeline** — expected signing, regulatory milestones, anticipated close date, and any interim operating restrictions [VERIFY based on jurisdiction and HSR/antitrust review status]
- **Existing integration playbooks** — prior PMI templates or lessons-learned from acquirer's previous transactions
- **Stakeholder map** — board, management, employees, customers, suppliers, regulators requiring communications

## Workflow

1. **Define governance structure** — Establish the IMO with an Integration Lead, Steering Committee, and functional workstream leads. Define decision rights, escalation paths, and meeting cadence (typically weekly workstream syncs, biweekly SteerCo).

2. **Build Day 1 readiness plan** — Identify all actions required for legal close and first day of combined operations:
   - Payroll and benefits continuity for target employees
   - IT system access (email, ERP, badge access) — determine cutover vs. parallel-run approach
   - Customer and supplier notification letters
   - Regulatory filings and post-close consents [VERIFY: specific filings depend on industry and jurisdiction]
   - External communications (press release, website updates, social media)
   - Interim operating protocols if close occurs before full integration

3. **Develop the 100-day plan** — Phase integration into three horizons:
   - **Days 1–30 (Stabilize):** Secure critical talent with retention agreements, confirm reporting structure, begin synergy baseline measurement, launch cultural assessment surveys
   - **Days 31–60 (Integrate):** Consolidate overlapping functions, migrate priority IT systems, align compensation and benefits frameworks, execute quick-win cost synergies (facilities, vendor consolidation)
   - **Days 61–100 (Accelerate):** Activate revenue synergy initiatives (cross-sell, pricing harmonization), finalize org design for remaining functions, establish unified KPI dashboards

4. **Assign functional workstreams** — For each workstream, document:
   - Workstream lead and team members
   - Key deliverables with due dates
   - Dependencies on other workstreams
   - Risks and mitigation actions
   - Synergy targets attributable to that workstream

5. **Build synergy realization tracker** — Create a tracker that maps each synergy line item to:
   - Responsible workstream and owner
   - Baseline metric and target metric
   - Milestone gates (initiative approved → implementation started → savings captured)
   - Variance reporting vs. deal-model assumptions
   - Monthly or quarterly reporting cadence aligned with SteerCo reviews

6. **Design communication and change management plan** — Sequence internal and external messaging:
   - Employee town halls and manager toolkits within first 48 hours
   - Customer outreach prioritized by revenue concentration
   - Supplier re-negotiation timeline
   - Regulatory and government affairs engagement where required [VERIFY]

7. **Establish integration risk register** — Catalog risks surfaced during diligence and new risks identified during planning. Score by likelihood and impact. Assign owners and review at each SteerCo.

## Output

The deliverable is a structured PMI plan document containing:

- **Governance charter** — IMO structure, roles, decision rights, and cadence
- **Day 1 readiness checklist** — Task-level items with owners, status, and completion criteria
- **100-day integration roadmap** — Gantt-style timeline with milestones across all workstreams
- **Workstream charters** — One-page scope, deliverables, and synergy targets per function
- **Synergy tracker** — Spreadsheet-ready format mapping line items to owners, milestones, and actuals vs. plan
- **Risk register** — Scored risk matrix with mitigation actions and owners
- **Communication plan** — Stakeholder matrix with message, channel, timing, and responsible party

## Quality Checks

- Every synergy line item in the deal model has a corresponding workstream owner and tracking mechanism
- Day 1 checklist covers legal, HR, IT, finance, and communications — no function is orphaned
- 100-day milestones are specific and measurable, not aspirational placeholders
- Retention agreements and key-talent actions are addressed in the first 30 days
- Change-of-control provisions from diligence are mapped to Day 1 or pre-close actions [VERIFY: review all material contracts flagged in diligence]
- Risk register reflects actual diligence findings, not generic PMI risks
- Communication plan sequences internal before external messaging and addresses regulatory notification requirements [VERIFY: industry-specific notification obligations]
- Synergy tracker distinguishes between cost synergies (typically higher confidence) and revenue synergies (typically longer realization horizon) with appropriate timing assumptions