In order to renew books online, you must access your library account.

Your login information consists of your name, institution code
(S# followed immediately by MSSU with no dashes or spaces), and
a PIN (at least 6 characters long) of your choosing. We suggest you
use your Missouri Southern PIN.
Once you have successfully submitted your login information you will see a series of boxes. One of these boxes will be labeled "Checked Out"
Clicking on this box will enable you to see a table that includes the items you have checked out with their due dates. This table has a renew column with check boxes. Checking the box next to an item will allow you to renew that item online.
Always check the due date after you've renewed your items. New due dates will appear if your renewal is successful.