CLICS is a CUNY-wide service that delivers books from one CUNY campus to another.
If the item you're interested in does not exist within any CUNY library, you can use Interlibrary Loan (ILL) to request the item.
RULE OF THUMB:
CUNY has the book → use CLICS
CUNY does NOT have the item (book or article) → use ILL (a.k.a. ILLiad)
Requesting an item (book or article):
Note: Adapted from CCNY's ILL LibGuide.
Requesting a book: