A machine tool has a tool holder mounted to a platform, and a plurality of legs for connecting the platform to a workpiece. Each leg has joint systems which allow each leg to rotate relative to the platform and the workpiece and are also actuatable to alter the inter-joint distance. By alterations in the inter-joint distances of the legs the position and orientation of the tool holder relative to the workpiece is controllable. Each leg also has an attachment foot for removably attaching the leg to the workpiece. The provision of separate attachment feet avoids the need for a dedicated base for the machine tool so that it can be used in-situ and in confined and obstructed working environments.
