Measurements of the Hadronic Cross Section and of Meson Transition Form Factors at BESIII for an improved Standard Model Prediction of (g-2)mu

The BESIII experiment at the Beijing tau-charm factory BEPCII recently has embarked on a series of form factor measurements with the goal to improve the hadronic vacuum polarization as well as the hadronic light-by-light contributions to (g-2)mu. The status of the flagship measurements and preliminary results are presented