The present application discloses a method of model-based measurement of semiconductor device features using a scatterometer system. The method includes at least the following steps. A cost function is defined depending upon a plurality of variable parameters of the scatterometer system and upon a plurality of variable parameters for computer-implemented modeling to determine measurement results. Constraints are established for the plurality of variable parameters of the scatterometer system and for the plurality of variable parameters for the computer-implemented modeling. A computer-implemented optimization procedure is performed to determine an optimized global set of parameters, including both the variable parameters of the scatterometer system and the variable parameters for the computer-implemented modeling, which result in a minimal value of the cost function. Finally, the optimized global set of parameters is applied to configure the scatterometer system and the computer-implemented modeling. Other embodiments, features and aspects are also disclosed herein.