The Political Communication Lab, consisting of faculty, graduate students, and postdoctoral fellows from Stanford University's Political Science department, was founded in 1998 by Shanto Iyengar to design and administer online experimental studies of media use and political behavior. The advantages of online experimentation became apparent in the aftermath of near-universal access to the Internet. 

PCL has collaborated with multiple researchers and media organizations to launch experimental studies of selective exposure to news, cross-national differences in public affairs knowledge and opposition to immigration, and most recently, the prevalence of affective polarization. These studies have resulted in numerous papers and books listed in the research page of this site.