Short answer: You assign a section from the delegate panel, and while there is no formal "take back" action, re-delegating or removing the person are the two ways to change who has access.
How to assign a section
Open the delegate panel from the portal dashboard.
Choose the section you want to hand over. Financials and Vision & Leadership cannot be delegated; they stay with the owner only.
Select the teammate you want to assign the section to.
Confirm. This grants that teammate both view and write access to the section's content.
Note: Every teammate can already see the status and completion percentage of all nine sections on the dashboard, including the two owner-only ones (shown locked, with a "Never shared" or "Only you" chip). Assigning a section is what opens up the actual content for them to edit, not the summary view.
If the teammate hasn't joined the portal yet, you'll need to invite them first; delegation only works once they're a member of the org.
Can I reassign or take it back?
You can hand a section to a different teammate at any time by assigning it to them the same way. Be aware of two things:
Re-delegating a section doesn't automatically revoke the previous assignee's access. They can still open and edit it unless you remove them from the org.
If you re-delegate a different set of sections to someone who's already active, accepting the new assignment can overwrite their earlier grants.
Warning: There's no clean "take back access to just this one section" action. The only confirmed way to fully strip a specific person's onboarding access is to remove them from the organisation, which removes all their access, and then re-invite them if you want them back with a narrower set of sections.
Also keep in mind that the "assigned to {name}" label you see on a section is session-only. After a reload or on another device, that label reverts to showing the owner's avatar, even though the delegate still holds their access. The section's actual progress and completion state are saved properly; it's only the "who it's assigned to" display that resets.