We briefly review some recent photoelectron spectroscopy (PES) studies of quasi one- and two-dimensional metallic systems. We discuss the spectral features of a metallic system, the expected fingerprints of the metal-insulator transition and some experimental and conceptual limitations of the single particle framework. This approach gives a satisfactory interpretation of PES experiments in 2D charge-density-wave materials. The single particle picture is however incompatible with experiments on 1D systems.