It is above all the 100% traditional craft and expertise, passed down from generation to generation, that gives Gruyère AOP its inimitable flavor and impeccable quality. The procedure for production of Gruyère AOP is strictly specified. Milk producers, cheese-makers and affineurs (maturers) respect each of its steps to the letter. This expertise has been guaranteed since 2001 through specifications approved by the Federal Office for Agriculture.