A review of friction theories relevant to the interaction between magnetic-recording-device components (hard, inelastic materials) and viscoelastic, polymeric materials used in the manufacture of flexible, magnetic tape is presented. Tabor's classical theory of adhesion with appropriate deformation and shear-strain rates, as well as Hegmon's theory of hysteresis friction, adequately describes the frictional behavior. Other sources of adhesional friction are stiction, meniscus, and microcapillary evacuation.