The wealth of information provided by full-field measurement techniques is very useful in experimental mechanics. Among different possible applications, full-field measurements can be used to identify parameters governing constitutive equations from heterogeneous strain fields. This keynote lecture first describes the different possible uses of such measurements. It then focuses on the virtual fields method which has been proposed to extract constitutive parameters from full-field measurements. Finally, the method is compared with the finite element model updating technique which is usually used for solving such a problem.