Since its inception, the Transportation Security Admin. (TSA) has focused much of its efforts on aviation security, and has developed and implemented a variety of programs and procedures to secure commercial aviation. More recently, TSA has taken actions to secure the nation's surface transportation modes. TSA funding for aviation security has totaled about $26 billion since FY 2004, and for surface transportation security activities, about $175 million since FY 2005. This testimony focuses on TSA¿s efforts to secure the commercial aviation system -- through passenger screening, air cargo, and watch-list matching programs -- and the nation's surface transportation modes. It also addresses challenges remaining in these areas. Ill.