Hadronic Contributions to R and g-2 from Initial-State-Radiation Data

I review the recent efforts to improve the precision of the prediction of the anomalous moment of the muon, in particular of the hadronic contribution of the vacuum polarization, which is the contribution with the largest uncertainty. Focus is given to the recent result for e+e- -> pi+pi- by the BaBar collaboration, obtained using events with radiation in the initial state.