The KFA programme to gather the necessary dosimetric and biophysical i
nformation to develop optimal dose calculation routines for conformal
proton radiation therapy is introduced. First experiments in a water p
hantom and with a plastic phantom are presented for incident protons o
f 175.5 MeV. Furthermore, the first detailed biophysical investigation
s on the RBE dependence of monoenergetic and energetically spread out
proton beams is described and the results are discussed.