Navigate to the relevant workspace and click on the 'Options' link on the top navigation bar.
Once in the workspace 'Options' section you can do the following:
Invite, remove and manage workspace Member permissions.
Change the workspace's name and create a welcome header for your workspace. You can add images, links, a welcome message and contact details, in fact anything that makes it instantly recognisable and informative to users.
Change the workspace's functionality. If you remove a function from a workspace it is only hidden from workspace members view, it's content isn't deleted. It can be re-enabled at any time and all of it's content will be intact.
Select a default settings for files, posts and tasks. Archive or delete workspaces.