Theo de Raadt is a software engineer, presently living in Calgary, Alberta, Canada. He is the founder and leader of the OpenBSD and OpenSSH projects.
de Raadt is noted for his confrontational manner, which has contributed to several disputes within the Open Source community, most notably his dispute with the NetBSD core team which led to the formation of OpenBSD.
Theo is notorious for stating his opinions regardless of what anyone else might think or any consequences. A multi-million-dollar US Defence Dept. grant to OpenBSD was cancelled following Theo's comments (in a radio interview) on the US intervention in Iraq.