Kim Eric Drexler (born April 25, 1955) is an American engineer best known for popularizing the potential of molecular nanotechnology (MNT), from the 1970s and 1980s. His 1991 doctoral thesis at Massachusetts Institute of Technology was revised and published as the book Nanosystems: Molecular Machinery Manufacturing and Computation (1992), which received the Association of American Publishers award for Best Computer Science Book of 1992.
Drexler participated in NASA summer studies on space colonies in 1975 and 1976. He fabricated metal films a few tens of nanometers thick on a wax support to demonstrate the potentials of high performance solar sails. He was active in space politics, helping the L5 Society defeat the Moon Treaty in 1980.