Employing a model system of paracetamol wet granulated with six common tablet binding agents, criteria for the evaluation of binder efficiency are established. Wetting of the substrate by a binder solution and binder film formation and deformation behaviour are major determinants of granule and tablet strength. Powdered binder pressure cohesion and binder-substrate pressure adhesion also influence binder efficiency, with probably the latter being more significant. Conversely, tablet friability is mainly influenced by binder film formation and deformation behaviour. The enhancement of binder efficiency by the incorporation of a wetting agent or a plasticizer into the formulation is explained in terms of the proposed mechanisms of binder adhesion.