M&A 100-Day Security Integration Plan
Plan the security integration of an acquired company from pre-close to Day 100 — privileged access, EDR, SIEM, identity federation, network interconnection gates and decommissioning — with owners, dates and milestone gates.
Template & sample only — a structured starting point with sample content, not legal, audit, certification or investment advice. Subscribers customise it with their own details and generate the document for their own work.
What this template gives you
- 29 integration tasks across pre-close, Day 1, Day 30 and Day 100, each with an owner, a due date and guidance on what done looks like.
- Covers network interconnection rules, identity federation, privileged access, EDR rollout, SIEM logging, vulnerability baseline, policy harmonisation, IR handover, third parties, data classification, awareness, cloud tenancy and decommissioning.
- A milestones table states the security gates that must be met before each step — especially before networks connect.
- Blocked material tasks surface as red flags, and an integration-progress score shows where you are.
Frequently asked questions
What should security do in the first 100 days after an acquisition?
Take control of privileged access and external exposure on Day 1, get visibility (EDR and logs into your SIEM) and a compromise assessment by Day 30, and only then connect networks, harmonise policies and decommission duplicates by Day 100. The order matters more than the exact dates.
When is it safe to connect the acquired network?
When written gates are met: high EDR coverage, logs flowing to your SOC, privileged accounts cleaned up, backups protected and a compromise assessment with no open findings. Connect specific, inspected flows rather than the whole network.
Is this a finished document I can rely on?
No. Every tool in this suite is a template with sample content. It gives you a structured, editable starting point and generates a document from your own answers, but it is not legal, audit, certification, investment or professional advice. Review and adapt the output, and have it checked by the appropriate specialist before you rely on it.
Who can use it?
The page and sample are public. Customising the template with your own details and exporting the generated document (Word, PDF, Markdown, CSV) is part of any PlayCISO paid plan. Your work is saved in your own browser.
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