The complete valence shell photoelectron spectrum of carbon disulphide has been studied using HeI, HeII and synchrotron radiation. In addition to the photoelectron bands associated with the X 2 g , A 2 u , B 2 Σ u + and C 2 Σ g + single-hole ionic states, several satellite features have been observed which are due to multielectron processes. The high resolution HeI and HeII excited spectra have allowed a detailed analysis to be made of the vibrational structure exhibited in the photoelectron bands corresponding to the single-hole and satellite states. The photoelectron spectra recorded with synchrotron radiation demonstrate that the inner valence region contains much complicated structure, and that distinct features are discernible up to a binding energy of at least 34 eV. Many-body Green's function calculations have been performed to evaluate the ionization energies and pole strengths associated with the main lines and satellite lines distributed throughout the valence shell region, and an interpretation of some of the experimental features is proposed, based upon these predictions.