Serge Klarsfeld is a Romanian-born French activist and Nazi hunter known for documenting the Holocaust in order to establish the record and to enable the prosecution of war criminals. Since the 1960s, he has made notable efforts to commemorate the Jewish victims of German-occupied France and has been a supporter of Israel.

A Nazi hunter is an individual who tracks down and gathers information on alleged former Nazis, or SS members, and Nazi collaborators who were involved in the Holocaust, typically for use at trial on charges of war crimes and crimes against humanity. Prominent Nazi hunters include Simon Wiesenthal, Tuviah Friedman, Serge Klarsfeld, Beate Klarsfeld, Ian Sayer, Yaron Svoray, Elliot Welles, and Efraim Zuroff.