The books in the Main Library stacks are organized by their Library of Congress (LC) call numbers, which are found in the catalog...

... and on the book's spine.

When searching the library catalog, you want to be sure to write down the complete LC call number in order to locate the book on the shelf.

Read the call number line-by-line to locate the book in the stacks:

Use the map of the stacks to find the location of the subject.

Fit the first two lines of the call number within the ranges provided on the stacks. For example, Z665 falls between Z8 and Z669.5, because numbers with fewer digits are shelved before numbers with more digits (e.g. both Z8 and Z9 will be shelved before Z89) so the book is shelved on this shelf:

Can't fit in the small space between the shelving? See this Research Guide for information about the Moveable Shelving in the Library.

Go alphabetically and numerically until you find the correct class (Z), subclass (Z) category (665) and subcategory (.L69) until you find the book:

If you have questions or would like assistance, stop by the Research Center on the Main Level.

Learn more about using Library of Congress Call numbers to browse for books on your topic with the call numbers research guide.

Finally, if you prefer, the Library can retrieve books that are in the Main Library for you using the "Request" book paging system. Here is a research guide for more information about requesting items from the library.