As an admin of a Space you are responsible for managing people on Knowa.
To access the administrator area, simply select the Space Settings dropdown in the Private Groups tab of your Space.
Select Manage People to view all the people in the space.
See also: Invite people to a Space
Edit a person's Permissions & Groups access
As an admin you can change the role a person has within a Space, promoting them to admin or limiting their access with Guest permissions.
You can also quickly view and edit which Groups they are a member of.
Simply select the ellipsis icon next to a user and select Manage Groups. Here you will be able to view and change their access.