We seek to understand the molecular basis of lubrication under water, particularly in biological systems. Biolubrication is an area of enormous importance, for instance, for tissue engineering in regenerative medicine, where the interfacial properties of scaffolding materials have not been extensively explored, or in developing treatments for eye or joint diseases which depend crucially on the friction.  Using the surface force balance we explore how surfaces modified with biological components like liposomes, hyaluronan and lubricin can reduce friction – this is believed to underlie the unique lubrication of the cartilage coating out joints.