One of the most important ways of processing polyethylene is film production. The many varieties of polyethylene and the variety of multilayer film structures allow film producers to meet the most demanding requirements. The properties of films are also naturally influenced by processing parameters. While data are available for single-layer films, no such data are available for multi-layer films. Nova researchers have tried to fill this gap. Of course, parameters not only need to be set, but also monitored and controlled. The principle is: measure what you can measure.