Plastics have developed into the most important class of packaging materials. Their relative impermeability for substances from the surroundings has great influence on the shelf life and the quality of the packed goods. At the same time the interaction between the contents and the various components of the packaging plays a decisive role.This particular book is indispensable in the search for the optimal plastic packaging. It facilitates the estimation of the influence on the goods which come from the surroundings and from the packaging. The authors do not restrict themselves only to the description of the phenomena of diffusion or transport in theory, but they show what they mean for practical applications.Food represents the central theme as main area of application for plastic packaging. It can be considered to be the "model substance" and the findings are to be applied to many other products and systems. The main rules and regulations for food packaging of the European Community and the United States are presented in this book. Furthermore the authors emphasize the testing methods for proving the mass transport and the sensory check of the quality of the products.