Map ownership first
- Who owns the content and who approves access?
- Which team uses it today and which team will support it after migration?
- Is the content project-based, department-owned, personal, archival, regulated, or shared externally?
- What content should be deleted, archived, or retained but not migrated into active collaboration spaces?
Choose the destination
- Use SharePoint sites for team-owned, department-owned, or process-owned content.
- Use Teams-connected sites when files are part of active collaboration and chat-based work.
- Use OneDrive for individual working files and personal drafts.
- Use archive storage or records repositories for stale content, legal hold, or retention-driven scenarios.
- Do not use a single giant SharePoint site as a replacement for a file server root unless there is a deliberate reason.
Design for findability
- Use clean site names, library names, hub navigation, metadata, search-friendly structure, and owner-visible descriptions.
- Avoid recreating extremely deep folder paths when metadata, separate libraries, or separate sites would be cleaner.
- Define permission boundaries at site or library level where possible; avoid excessive folder-level uniqueness.
- Create user guidance for OneDrive sync, Teams files, sharing links, version history, and search.