A tourniquet system having an optical tourniquet interface for safe personalization, comprising: a tourniquet cuff assembly including: a tourniquet cuff (2, 206) having an inflatable bladder adapted for connection to a tourniquet instrument, a contactlessly-readable instrument symbol identifying one type of tourniquet instrument from a plurality of types of tourniquet instruments, and contactlessly-readable personalization data representing a value of a personalization parameter for safe operation of the tourniquet cuff (2, 206) when connected to the identified type of tourniquet instrument; and a tourniquet instrument including: an optical tourniquet interface communicating with a pressure controller and operable for contactlessly reading and authenticating the contactlessly-readable instrument symbol associated with the tourniquet cuff (2, 206) if it matches stored instrument authentication data, and further operable for contactlessly reading the contactlessly-readable personalization data associated with the cuff (2, 206), wherein the optical tourniquet interface is adapted to present in a form perceptible to a user the value of the personalization parameter if the contactlessly-readable instrument symbol has been authenticated; a safe transfer key which is operable by the user to manually selectively transfer the presented value of the personalization parameter to the pressure controller only if the pressure controller is inoperable; and the pressure controller releasably connectable to the tourniquet cuff (2, 206) and responsive to the transferred value of the personalization parameter, wherein the pressure controller is operable for automatically controlling a level of pressure in the connected tourniquet cuff (2, 206) during a pressure control time period. a tourniquet cuff (2, 206) having an inflatable bladder adapted for connection to a tourniquet instrument, a contactlessly-readable instrument symbol identifying one type of tourniquet instrument from a plurality of types of tourniquet instruments, and contactlessly-readable personalization data representing a value of a personalization parameter for safe operation of the tourniquet cuff (2, 206) when connected to the identified type of tourniquet instrument; and a tourniquet instrument including: an optical tourniquet interface communicating with a pressure controller and operable for contactlessly reading and authenticating the contactlessly-readable instrument symbol associated with the tourniquet cuff (2, 206) if it matches stored instrument authentication data, and further operable for contactlessly reading the contactlessly-readable personalization data associated with the cuff (2, 206), wherein the optical tourniquet interface is adapted to present in a form perceptible to a user the value of the personalization parameter if the contactlessly-readable instrument symbol has been authenticated; a safe transfer key which is operable by the user to manually selectively transfer the presented value of the personalization parameter to the pressure controller only if the pressure controller is inoperable; and the pressure controller releasably connectable to the tourniquet cuff (2, 206) and responsive to the transferred value of the personalization parameter, wherein the pressure controller is operable for automatically controlling a level of pressure in the connected tourniquet cuff (2, 206) during a pressure control time period. an optical tourniquet interface communicating with a pressure controller and operable for contactlessly reading and authenticating the contactlessly-readable instrument symbol associated with the tourniquet cuff (2, 206) if it matches stored instrument authentication data, and further operable for contactlessly reading the contactlessly-readable personalization data associated with the cuff (2, 206), wherein the optical tourniquet interface is adapted to present in a form perceptible to a user the value of the personalization parameter if the contactlessly-readable instrument symbol has been authenticated; a safe transfer key which is operable by the user to manually selectively transfer the presented value of the personalization parameter to the pressure controller only if the pressure controller is inoperable; and the pressure controller releasably connectable to the tourniquet cuff (2, 206) and responsive to the transferred value of the personalization parameter, wherein the pressure controller is operable for automatically controlling a level of pressure in the connected tourniquet cuff (2, 206) during a pressure control time period.