Speaker : Winnifried Wollner Abstract: Adaptive FEM for solution of elliptic optimization problems with restrictions on controls This talk will introduce an error-estimator for optimal controlproblems of elliptic PDE with respect to box constraint control. First we will give a brief introduction into the optimal control problem considered. We will continue with deriving two slightly different error estimators, and discuss some practical problems concerning the evaluation of the introduced terms. Finally some numerical results will be presented.