Magnetic reconnection at a three-dimensional null point is the natural extension of the familiar two-dimensional X-point reconnection. Three dimensional null points are found in abundance in the solar corona, where they are thought to be an important feature with regards to the coronal heating problem. A model is set up here for reconnection at a 3D magnetic null point, by solving the kinematic, steady, resistive MHD equations in its vicinity. A steady magnetic field is assumed, as well as the existence of a localised diffusion region surrounding the null point. Particular attention is focused on the way that the magnetic flux changes its connections as a result of the reconnection process. The nature of the flows and the reconnection is fo...