This thesis examines the phenomenon comedian Stephen Colbert dubbed “truthiness” as it pertains to representations of authenticity in the documentary film genre. This thesis identifies several “markers of authenticity,” such as voice-over narration and confessional interviews, which have come to represent trustworthy representations of reality in the documentary form. This thesis also provides a content analysis of the markers’ use in five carefully selected contemporary documentaries, including Super Size Me (Spurlock, 2004) and Bowling for Columbine (Moore, 2002). The purpose of the study is to create a more comprehensive definition of the word truthiness as it pertains to the documentary film genre. The results of the study show that truthiness exists when a marker of authenticity is used to support the articulation of the documentarian’s viewpoint at the expense of a subject’s authenticity. The results of the study also show that truthiness exists when any marker of authenticity is used to convey a secondary meaning for comedic or ironic effect