This longitudinal study reports on the development and evaluation of a narrative intervention aimed at increasing human papillomavirus (HPV) vaccination among college women. The prevention of HPV is a public health priority due to its pervasiveness and relationship to cervical cancer, the second leading cause of cancer deaths among women worldwide. Pilot work utilizing culture-centric narrative theory guided development of the intervention content. Exemplification theory led to hypotheses comparing communication sources of the narrative messages (peer only, medical expert only, or a combination of the two source types) in a four-arm randomized controlled trial (N = 404; 18-26 year olds). The combined peer-expert narrative intervention nearly doubled vaccination compared to controls (22% vs. 12%). The pragmatic goal of increasing HPV vaccination and the theoretical predictions about message source were supported. As predicted, the inclusion of peer and medical expert sources plays a critical role in promoting HPV vaccination among college women. Furthermore, the intervention increased HPV vaccination by increasing vaccine self-efficacy and intent. Theoretical and practical implications for designing effective HPV vaccine messages are discussed.