Developments in spin-polarized internal targets for storage rings have perm
itted measurements of 197 MeV polarized protons scattering from vector pola
rized deuterons. This work presents measurements of the polarization observ
ables A(gamma), iT(11), and C-gamma,C-gamma in proton-deuteron elastic scat
tering. When compared to calculations with and without three-nucleon forces
, the measurements provide further evidence that three-nucleon forces make
a contribution to the observables. This work indicates that three-body forc
es derived from static nuclear properties appear to be crucial to the descr
iption of dynamical properties.