In searching for members of Congress, gathering biographical information about the individual can be helpful, especially: variant names, state represented, dates in office, key legislation in which the person participated, and activities in which he or she engaged. As individuals are not always identified in photographs showing activities, it is helpful to have an identified portrait, possibly from a published source, to use as visual reference in order to recognize the individual in question.

While many images relating to the U.S. Congress have been digitized and individually described, additional images may be found in the portion of the collections that are not individually described and digitized. Generally, making a visit to the Prints & Photographs Reading Room is the best means for reviewing the holdings for relevant images. (Use the link at the bottom of this page for more information about visiting the reading room and service from a distance.)

The information below discusses techniques for searching for online images, as well as tools for doing on-site research.