  The quasi-one-dimensional metallic system BaVS3 with a metal-insulator
transition at T_MI=70 K shows large changes of the optical phonon spectrum, a
central peak, and an electronic Raman scattering continuum that evolve in a
three-step process. Motivated by the observation of a strongly fluctuating
precursor state at high temperatures and orbital ordering and a charge gap at
low temperatures we suggest a concerted action of the orbital, electronic, and
lattice subsystems dominated by electronic correlations.
