Charles B. Curtis (born April 27, 1940) is an American lawyer, currently Board member of Energy Futures Initiative Foundation, Member of Energy Futures Initiative International Advisory Committee,Board Member Executive Committee, Keep Our Republic Foundation, former senior advisor (nonresident) to the Center for Strategic and International Studies,2012 through 2024,vice chair of the United States Department of State's International Security Advisory Board, 2011 through 2017, former member of the National Academies Intelligence Science and Technology Experts Group, and President Emeritus of the Nuclear Threat Initiative (NTI), a non-profit organization working to reduce the threats from nuclear, biological and chemical weapons.

He has held positions on the staff of the U.S. House of Representatives, the U.S. Treasury Department, and the Securities and Exchange Commission.

From May 1967 to June 1971 he was special counsel to the Division of Trading and Markets; and Chief of the Branch of Regulation and Inspection of the Securities and Exchange Commission.

From 1971 to 1976 he was a professional staff member of the U.S. House of Representatives Committee on Interstate and Foreign Commerce, where he served as lead energy, securities and consumer counsel.

He led the development of two key programs that led to major U.S. government efforts working with the Russians to secure their nuclear material, and working with the Russians to secure and repatriate Soviet-origin highly enriched uranium, the easiest material to make a terrorist nuclear device with, scattered around the world in former Soviet republics and client states.

The Nuclear Threat Initiative was founded in 2001 and resulted from Curtis teaming with former Senator Sam Nunn and CNN founder Ted Turner to form a charitable organization focused on issues that were previously the sole domain of governments.