The apparatus includes a source of treatment radiation which is arranged to generate radiation at one of a plurality of radiation parameters (such as power levels), a control unit and a base unit. The control unit is arranged to removably dock with the base unit and includes a sensor which can sense one of a plurality of skin parameters, and an actuator for enabling a user to interface with the control unit. The control unit operates in a sensing mode, in which the control unit is undocked from the base unit to sense a parameter of skin to be treated (such as skin tone), and a control mode in which the control unit is docked to the docking unit and is arranged to select the power level of the radiation generated by the source.