The purpose of the CDC’s i know campaign is to promote dialogue about HIV/AIDS among African American men and women aged 18 to 24, which can ultimately help reduce HIV-related stigma and increase preventive behaviors, such as consistent condom use. The campaign will disseminate its messages via multiple channels including: • the i know campaign website • Social media channels (e.g., Facebook) • SMS text messages and • Radio The i know evaluation is monitoring campaign implementation activities. The evaluation is assessing campaign exposure and reach with its target audience. The impact evaluation is examining the extent to which: • campaign messages are shared with others (e.g., retweets from twitter); • audiences engage in dialogue around campaign messages (e.g., comments on Facebook status updates); • audiences exposed to campaign messages seek out additional information (e.g., click thrus to “i know website”). These data are collected by: Linguastat, an on-line media monitoring service that tracks twitter, Facebook, Youtube, blogs, and online news sources; Dewey Digital, responsible for the SMS text messaging, Urchin, a google analytics software tool for website traffic, and the CDC media team and campaign partners. In this panel session, presenters will describe the campaign’s formative research, its theoretical framework, how constructs were operationalized for evaluation, campaign strategies and extended reach via key partner involvement, evaluation methods, and baseline and five-month post-launch data.