Multi‑Vendor Collaboration — Playbook (One‑Pager)

Joint delivery patterns

Principles

Vendor‑neutral; outcome‑focused; clear RACI
Single Point of Contact (SPOC) per supplier; escalation ladder documented
Shared Decision Log and RAID; common change/maintenance windows

Operating model

Governance	Light RACI; weekly sync; joint risk review
Interfaces	Telemetry sharing; who executes which step; evidence capture
Change	CAB etiquette; dry‑run and rollback rehearsed
Comms	Client Comms Lead; holding statements; coordinated notices

IR example (M365 + MSP + backup)

We lead triage; MSP isolates hosts; SaaS owner purges/ZAP; backup provider confirms immutability and clean restore points; go/no‑go captured in Decision Log.