The forces acting between colloidal particles and between surfaces are of utmost importance for determining the behaviour in dispersed systems and adhesion phenomena. Several techniques are now available for directly measuring these surface forces and in this review we focus on five different methods. These include three techniques for measuring forces between solid surfaces; the interferometric surface force apparatus, known as the SFA, the atomic force microscope (AFM) with a colloidal probe, and a novel instrument which does not utilise optical techniques. We also describe two different methods that can be used for measuring forces between "soft" interfaces, the thin-film-balance for foam, emulsion and solid/fluid/fluid films, and the osmotic stress method, commonly used for biological and emulsion systems. The advantages and limitations of each technique are discussed and typical results are presented.