While research has found that the presence of an interviewer can influence respondents’ answers to questions, less attention has focused on the potential impact that other respondents may have on survey responses as might occur in group-administered settings. In assessing topics related to group culture and peer-pressure, the presence or absence of other group members when completing the survey may influence responses. Such influences may be stronger in a tight-knit group like the United States military where unit cohesion and trust are critical to mission success. In this study, survey responses to items concerning group culture and influence when asked on a paper-pencil, group-administered survey were compared with responses on an individually-administered, online survey. The Department of Defense and U.S. Coast Guard authorized the 2011 Health Related Behaviors Survey to explore the prevalence of a number of behavioral health issues including the military culture of substance use, the presence of peer pressure to use substances, and the stigma associated with receiving mental health services. Personnel from a few key military installations from the Army, Navy, Marines, and the Coast Guard were randomly assigned to one of the administration modes. Respondents were assured anonymity for each mode. Group-administered paper-pencil survey respondents indicated greater stigma of receiving mental health care and a stronger military culture of substance use than did respondents in the Web-based mode.