The third IEEE Multiconference on Systems and Control (MSC 2009) was held in Saint Petersburg, Russia, between July 8-10, 2009. The conference was governed, organized, and sponsored by the IEEE Control Systems Society (CSS) and hosted by the Institute for Problems in Mechanical Engineering that was affiliated with the Russian Academy of Sciences. The event included two separate annual conferences of the CSS, the 18th IEEE International Conference on Control Applications (CCA 2009). It was successful with 295 registered participants from 46 countries. The technical program for regular sessions consisted of 334 contributed and invited papers out of 518 submitted, with 320 papers presented. There were 56 regular sessions and four plenary sessions. More than 60 participants from developing countries received support from CSS Travel Support and Conference Support programs that provided aid for the registration fee, lunches, and the banquet.