Master of Science in Computer Science, Helsinki University of Technology, Espoo, Finland, 1994.
Founder, Chief Executive Officer, Chief Technology Officer New Generation Software Oy Ltd, Espoo, Finland, 1988—1993. Founder, Chief Executive Officer, Chief Technology Officer, chairman SSH Communications Security Corp, Helsinki, Finland, since 1995. Founder Tatu Ylönen Oy Ltd, Espoo, Finland, since 2005, Chief Executive Officer, since 2005.
Member of Institute of Electrical and Electronics Engineers, Association Computational Linguistics, Materials Information Society, International Society Optical Engineering, American Association Artificial Intelligence, Association Computing Machinery.