This course introduces the theory and numerical modelling of ocean circulation. This includes the theory of steady and time-dependent large-scale circulation, effects of earth's curvature, wind-driven Sverdrup circulation, western boundary currents, eastern boundary upwelling, effects of buoyancy forcing, wind- and buoyancy-forced circulation in the thermocline. The course also reviews theoretical models of ocean circulation, including shallow water, barotropic, quasigeostrophic, and primitive equation models; adjustment times, internal length and time scales; the role of advection, bathymetry and coastlines; global models, basin models, regional models.