Abstract: A castor comprises a castor body (12), a castor wheel (14), and a bearing block (20) for supporting the castor wheel relative to the castor body. The bearing block is selectively mountable in each of a first and a second orientation relative to the castor body. In the first orientation of the bearing block relative to the castor body, the castor wheel is arranged to be braked in response to the application of a load applied to the castor. In the second orientation of the bearing block relative to the castor body, the castor wheel is arranged to be braked in the absence of a load applied to the castor.