The nine Affiliated Libraries contain significant campus collections. University of California Office of the President (UCOP) statistics (2003-04) show that 17% of total volumes and 29% of currently received serials in UC Berkeley libraries are held by Affiliated Libraries.
The Affiliated libraries are typically connected to particular departments, professional schools, or organized research institutes. These libraries are administratively separate from The Library system and from each other. The primary mission of the Affiliated Libraries is to support the teaching and research needs of their respective organizations. Their collections reflect these specialized concerns.
The Affiliated Libraries have developed in-depth subject emphases and may use their own subject headings and classification schemes. Some of the Affiliated Libraries collections are currently represented in the University's Melvyl catalog, in The Library's OskiCat catalog, or both.