Ruzena Bajcsy - University of California, Berkeley (UC Berkeley), CITRIS In this presentation, first I review the ancient history feedback control that goes back Egypt, 3 centuries before Christ. Then I jump to the 1960s which has seen a great deal of activities spurred after the WW2. R. Kalman in 1960 built a new theory of linear systems motivated by Wiener and Shannon. The concept of reachability (performance boundaries) were introduced by Roxun in his PhD thesis from Univ. of Bueno Aires, in Argentina in 1998. Later Bertsekas at MIT in 1971 formulated the reachable sets as we use it today. I will try to systematically show the further development of these boundary conditions as developed by Sastry in the 80s and Tomlin in the 90s up to now.