Calculations have been made of the influence of the number of valence-shell electrons of a sulphur atom on the binding energies of 1sand 2pelectrons. These energies are related to the chemical shift of the Kαline and of the absorption edge as measured by electron spectroscopy. The present calculations extend previous work by using the full self-consistent-field technique and by considering both the parent and daughter systems. In so far as the flow of charge in a chemical bond may be related to the effective (fractional) number of valence electrons, this shows that information about the degree of ionic character can be obtained from accurate experimental observation of these phenomena. Estimates are made for sulphides, sulphites, and sulphates. For the full application of the method very high experimental precision is necessary.