Abstract: The invention is directed generally to a method and system for controlling the temperature of a fluid, i.e., warming or cooling a fluid, and more particularly, to a method and system for warming a fluid to be delivered to the body of a patient. In a preferred embodiment, a method and system for warming a fluid to be delivered into the body of a patient is provided and may include a controller and a fluid delivery-line. The fluid delivery-line may include an insulative tube and a fluid delivery tube positioned within the first tube and for communicating a fluid from a source to a destination. The fluid delivery-line may also include at least one thermal sensor positioned proximate the fluid delivery tube, a heating element positioned proximate the fluid delivery tube and a thermal medium positioned between the first tube and the second tube.