Martin Edward Hellman (born October 2, 1945) is an American cryptologist and mathematician, best known for his invention of public-key cryptography in cooperation with Whitfield Diffie and Ralph Merkle.

[2][3] Hellman is a longtime contributor to the computer privacy debate, and has applied risk analysis to a potential failure of nuclear deterrence.

[5] From 1968 to 1969 he worked at IBM's Thomas J. Watson Research Center in Yorktown Heights, New York, where he encountered Horst Feistel.

An audio recording survives of their review of DES at Stanford in 1976 with Dennis Branstad of NBS and representatives of the National Security Agency.

The authors of the book examine questions such as: How can we overcome the inexorable forces leading toward a clash between the United States and the Soviet Union?

His website NuclearRisk.org has been endorsed by a number of prominent individuals, including a former director of the National Security Agency, Stanford's President Emeritus, and two Nobel Laureates.

Hellman is a member of the Board of Directors for Daisy Alliance, a non-governmental organization based in Atlanta, Georgia, seeking global security through nuclear nonproliferation and disarmament.

[20] Also in 2011, Hellman was made a Fellow of the Computer History Museum for his work, with Whitfield Diffie and Ralph Merkle, on public key cryptography.