Read this guide for instructions on how to edit or remove an administrator from an organisation profile.
1) Go to My Organisations
Click on Recruiter Dashboard from the Your Do-it drop menu:
And on My Organisations, find the organisation you want, then click on the Administrator button:
Here you'll see the list of the other administrators of this organisation.
2) Find the administrator you want
In the list, find the name of the administrator you're looking for, and click either Edit or Delete:
Here you can change the permissions of this administrator. See here for guidance on what permissions mean.
If you click Delete you'll be asked to confirm you want to do this, or cancel the action.
Note, this will NOT delete a user from the site, or delete anyone's account. If you delete an administrator, they will be completely removed from that organisation and its opportunities, but will retain everything else on their account.