The results of a systematic study on two misfit layer compounds: (PbS)1.18(TiS2) and (PbS)1.18(TiS2)2 by X-ray Photoelectron Spectroscopy are reported. The core levels and the valence band spectra have been analysed and compared with the non-intergrowth samples (PbS) and (TiS2). In order to shed light on the stabilization of misfit layer compounds, we performed a comparison between theoretical (EHT-TB method) and experimental results on the mono-layer misfit compound. The chemical shifts or/and the broadenning of the core level peaks have been discussed in terms of initial and final states, the former based on the possible charge transfer between PbS and TiS2. We have shown how the XPS valence band is modified by the PbS-TiS2 interactions by using calculated densities of states. © 1998 Elsevier Science B.V. All rights reserved.