Public involvement in alerting officials of suspicious and potentially harmful activity is critical to the overall security of a transit system. As part of an effort to get passengers and the public involved, many transit agencies have security awareness campaigns. The objective of this research is to learn how transit agencies seek to make security awareness campaigns effective and to explore how they measure the effectiveness of such campaigns, if at all. This research project includes data from case studies of five major agencies that provide transit service in the San Francisco Bay Area region of California. The case study data consist of descriptions of the types of security awareness campaigns the agencies have implemented, the goals of the campaigns, and how they seek to make their campaigns effective, as well as whether and how these agencies measure and determine the effectiveness of their campaigns. One positive finding of this research is the consistency with which Bay Area transit organizations address the need for passenger awareness as part of their overall security program. However, none of the five agencies analyzed for this study measures the effectiveness of their campaigns. Although they all have a similar goal—to increase passenger awareness about security issues—little evidence exists confirming to what extent they are achieving this goal. Suggestions are offered for using outcome measurements to provide a reasonable indication of a campaign's effectiveness by capturing the public's response to a campaign.