Hydrodynamic bearings exploit the properties of pumping action in a fluid to support a bearing load. Conventionally, the pumping action is provided by grooved surfaces in a bearing surface of the bearing. The provision of grooves leads to functional and practical problems, though. The action of grooves on a lubrication material leads inevitably to shear stress being exerted in the fluid. This has a detrimental effect on the load performance of a hydrodynamic bearing. In practical terms, the accurate manufacture of grooves is onerous. This application discusses a way of producing a hydrodynamic bearing using a portion of a bearing surface with an interleaved pattern of materials, wherein the materials have alternate high and low (or zero) fluid slip characteristics. The varying fluid slip characteristic of the surface induces a pumping effect analogous to that provided by a grooved surface.