  The 11th workshop, Descriptional Complexity of Formal Systems 2009, is taking
place in Magdeburg, Germany, on July 6-9, 2009. It is jointly organized by the
IFIP Working Group 1.2 on Descriptional Complexity and by the Faculty of
Computer Science at the Otto von Guericke University Magdeburg. This volume
contains the papers of the invited lectures and the accepted contributions.
