This document provides an overview of the Centers for Disease Control and Prevention's (CDC) use of social media. It discusses CDC's strategy of using multiple social media formats like Facebook to disseminate health information to diverse audiences. It highlights CDC's Facebook page which has over 54,000 fans and is used to share information about public health issues like H1N1 flu. The document also describes CDC's "I Know" campaign on Facebook to promote HIV prevention among young African Americans. It reviews CDC's social media comment policy and efforts to ensure compliance with Section 508 accessibility standards.