Stephen Joseph "Steve" Lukasik (March 19, 1931 – October 3, 2019) was an American physicist. He worked in multiple high-level defense and scientific related jobs for advancing the technologies for national defense. He was the second longest serving Director of DARPA - the Defense Advanced Research Projects Agency.
He was also the first Chief Scientist of the Federal Communications Commission where he created its Office of Science and Technology and which facilitated the commercial deployment of new technology that included spread spectrum technology. He was born in Staten Island, New York.
Lukasik died on October 3, 2019 in Fairfax, Virginia of respiratory failure at the age of 88.