R.R. Bowker is the U.S. ISBN Agency in the United States, responsible for assigning ISBNs as well as providing information and advice on the uses of the ISBN system to publishers and the publishing industry in general. R.R. Bowker is charged by the International ISBN Agency with the collection of bibliographic data on titles published in the U.S. This title data is found in the databases of Books in Print.

In addition, R.R. Bowker also serves as the SAN Agency (Standard Address Number for publishing industry shipping addresses), the ISMN Agency (International Standard Music Number for sheet music), the DOI Registration Agency (Digital Object Identifier), and offers EAN bar code services.