Controlling authorization within computer systems

A terminal device for controlling provision of data, said terminal device comprising:

• a login data store configured to store one or more instances of login data and having a locked state and an unlocked state;
• circuitry to transmit, from the terminal device, a request to access a service when the user is logged onto the terminal device;
• receiving circuitry configured to receive a request for a target instance of login data from a requester and, if said login data store is in said unlocked state and said target instance of login data is stored within said login data store, then automatically to provide said target instance of login data to said requester without requiring any user input;
• detecting circuitry configured to detect if a personal computing device is proximal to said terminal device,
• circuitry to determine if said personal computing device has an authorized state or an unauthorized state;
• and
• switching circuitry configured:
• if said personal computing device is proximal to said terminal device onto which the user is logged,
• when said personal computing device is determined to be in said authorized state and said login data store is in said locked state, then to switch said login data store from said locked state to said unlocked state, and
• when said login data store is in said unlocked state and said personal computing device switches from said authorized state to said unauthorized state, then to switch said login data store from said unlocked state to said locked state.