The invention relates to a surgical robot system comprising a robot arm (8) installed on a substructure (1), a first control instance (16) for producing control commands for the robot arm (8) on the basis of user inputs, and a second control instance (18), which receives the control commands from the first control instance (16) and checks the control commands with respect to whether the execution of the control commands by the robot arm (8) requires the robot arm to leave a specified occupied space (21, 22) of the robot arm (8) and releases a control command for execution by the robot arm (8) at most to the extent to which the control command can be executed without the robot arm leaving the specified occupied space (21, 22, 30).