The sulfur and chlorine centers in sensitizing dyes and surface-modifying agents of importance to the photographic system were characterized by S and Cl K-edge X-ray absorption spectroscopy (XAS). The K-edge spectra of these compounds reveal sharp, characteristic absorption features that provide direct information about the local electronic and geometric environment of the absorber centers. In particular, a sharp, intense pre-edge feature at 2470-2472 eV is observed in the spectra of compounds containing exocyclic S (thione or thiol) that has no counterpart in the spectra of thiazole-containing (cyclic S) compounds. Single-crystal polarized spectra reveal that the edge features of these compounds exhibit a strong orientational dependence, permitting the assignment of some of the observed features. The exocyclic S pre-edge feature was assigned to a S 1s --> pi* transition, while the predominant spectral feature at 2473-2474 eV observed in all of the S K-edge spectra was found to be polarized along the C-S bond direction and assigned to a S 1s --> sigma* transition. Dramatic changes in the sulfur-ligand spectral features are produced from complexation with Ag and Au atoms, which permits the distinction of covalent vs ionic interactions with the metals encountered in photographic systems. Covalent metal interaction with an exocyclic S-containing ligand resulted in the disappearance of the low-energy pi* pre-edge feature, while the intensity of the predominant sigma* feature in all compounds investigated was greatly enhanced upon complexation with Au and Ag metals. In contrast to the uncomplexed ligands, this predominant feature was found to be most intense for polarizations along the S-metal direction and perpendicular to the C-S bond, indicating a direct bonding interaction with the Au metal, as seen, for example, in a bis(ethylenethiourea) Au(I) complex. The K-edge spectra of Cl centers, present as substituents on the ring system of the dye molecules, exhibit a single predominant feature at approximately 2825 eV, which is characteristic of the terminal C-Cl environment and is relatively insensitive to structural changes in the dye systems more remote from the Cl centers. Single-crystal measurements revealed that this spectral feature is polarized predominantly along the C-Cl bond direction, indicating that it is due primarily to a Cl 1s --> sigma* transition with some contribution from a lower-intensity transition to a near-lying pi-symmetry orbital.