We give an overview of use of the transmission electron microscope (TEM) in the characterisation of metallic multilayers. The different types of structural information available from phase and diffraction contrast imaging, as well as the various diffraction modes, are described. The particular usefulness of techniques such as the Fresnel fringe method for multilayer interface characterisation is emphasised. The use of analytical TEM and scanning TEM (STEM) for chemical characterisation is also covered. Special considerations and methods applying to the study of magnetic materials are briefly considered. All points covered are illustrated with examples from the recent literature.