Lee has served as the CEO of eOn Communications Corporation since 2003 and has performed as the Chairman of the board of that company since 1991. From 1985 to 1988, Lee was President and Chairman of Data Technology Corporation, a computer peripheral company. Prior to 1985, he was Group Executive and Chairman of the Business Information Systems Group of ITT Corporation. He was also President of ITT subsidiary ITT Qume, formerly Qume Corporation, a computer systems peripherals company which Lee co-founded in 1973 prior to its acquisition by ITT Corporation in 1978.