The photo-absorption spectrum of (CH3)2S has been measured using synchrotron radiation in the range 5.0-11 eV (250 > λ > 110 nm). Electronic state assignments have been suggested for each of the observed absorption bands incorporating both valence and Rydberg transitions. Four Rydberg series have been assigned converging to the ionisation potential limit 8.686 eV. Rydberg orbitals of each series are classified according to the magnitude of the quantum defect (δ). The measured vacuum-ultraviolet (VUV) cross-sections are used to derive the photolysis rate of (CH3)2S in the terrestrial atmosphere.