Presentations on tire aging at recent industry conferences indicate that the industry is beginning to accept what only several years ago it claimed was not possible-a scientific basis for tire expiration dates. Foundational to this acceptance is agreement from the tire makers, NHTSA, and Ford Motor Company that static oven aging in a lab can mimic thermo-oxidative aging found in tires removed from the field-an important step toward a regulatory performance standard. Other presentations have addressed specific tire components and properties that affect tire aging degradation. The unspoken message has been loud and clear: tire age matters and regulation appears inevitable.