We developed an electronic medical record (EMR)-based HPV vaccine decision support intervention targeting clinicians, (immunization alerts, education, and feedback) and families (phone reminders and referral to an educational website). Through telephone surveys completed by 162 parents of adolescent girls, we assessed the acceptability of the family-focused intervention and its effect on information-seeking behavior, communication, and HPV vaccine decision-making. The intervention was acceptable to parents and 46% remembered receiving the reminder call. Parents reported that the call prompted them to seek out information regarding the HPV vaccine, discuss the vaccine with friends and family, and reach a decision. Parents whose adolescent girls attended practices receiving the clinician-focused intervention were more likely to report that their clinician discussed the HPV vaccine at preventive visits. The results of this study demonstrate the acceptability and potential impact on clinical care of a comprehensive decision support system directed at both clinicians and families.