Electronic absorption, magnetic circular dichroism, and (polarized) phosphorescence and phosphorescence excitation spectra are reported for dithiosuccinimide, dithioglutarimide, and dithiocamphorimide and their N-methyl derivatives. The theory of Engelbrecht et al. (Spectrochim. Acta 1975, 31A, 507) for magnetic circular dichroism (MCD) in singlet-triplet transitions is extended to show that not only the shape but also the magnitude of the MCD is of help in characterizing such transitions. The weak shoulder at similar to 500 nm in the absorption spectra of the dithioimides is, using C-2v symmetry labels, identified as the S-0 --> B-3(1)(n pi*)) transition. Its polarization is almost exclusively (similar to 99%) parallel to the line C(S)-C(S) in the dithioimide chromophore, Presumably the responsible tripler sublevel derives its radiative character from spin-orbit coupling to the third excited singlet state (S-3), B-1(2)(pi pi*) The radiation from the other active sublevel is polarized along the C-2 axis of the chromophore. From the absorption spectra and the excitation polarization data, which were obtained via the photoselection method, the lowest excited singlet state is assigned as B-1(1)(n pi*), S-2 as (1)A(2)(n pi*). The experimental findings are consistent with C-2v symmetry for dithiosuccinimide, and C-s symmetry for the chromophore in N-methyldithioglutarimide and N-methyldithiocamphorimide. The data indicate that at 77 K the phosphorescent state, B-3(1)(n pi*), is not appreciably out-of-plane distorted with respect to the ground state.