During the last six years we have carried out a series of ground-based microwave measurements on agricultural fields. Bare soils, corn (maize), wheat, sugar-beet, potatoes, grass, canola (rape), oat, and rye were observed under various conditions and phenological stages. Our calibrated radiometer-scatterometer system, RASAM, operates at frequencies between 3 and 11 GHz. The brightness temperature was measured at horizontal and vertical polarization, and the back scattering coefficient at HH, W, HV, and VH polarization, all at incidence angles from 0° to 70°. In addition we measured soil and vegetation parameters. The data are stored in our signature data base.