Optimized packaging should use a minimum amount of material to efficiently protect the packaged product from spoilage and unwanted interaction with its environment. It should also be economically manageable for the subsequent steps in its lifecycle, including transportation, handling, storage and use. Product image and efficient usage are closely related to the success of a product and the opening behavior is an increasingly important success factor in which the peel properties of the sealing material are of considerable influence. The sealing behavior has an equally crucial impact on the cost effectiveness of the packaging process. New and improved test methods provide valuable assistance in optimizing opening forces and selecting a suitable sealing material. (C) Koninklijke Brill NV, Leiden, 2011