The introduction of legislation to minimize packaging waste requires consumer goods manufacturers to use lighter-weight materials and increase the use of recycled materials. This is demanding that machinery manufacturers provide highly fl exible machines and tooling capable of handling these materials and new package designs. However, the ability of manufacturers to achieve this is all but prevented by a lack of fundamental understanding of machine-material interactions and an ability to generate such understanding. One way to overcome this is to use advanced simulation tools to represent the whole system including machine, process, materials and product.A fi nite element-based simulation has been created to represent the in-process behaviour of a packing system. The simulation focuses on the critical transition between fl attened and erected states of a carton. In order to successfully simulate such a complex process, there are a number of major challenges concerning the representation of packaging materials and their properties, changing material behaviour during processing, machinery simulation and process modelling (simulating the interfacial interactions that take place during processing).The application of the whole-system simulation for the purposes of improved design and operation are discussed with respect to four activities: design and setup of tooling, determination of optimal process settings, specifi cation of material properties and the design of the pack. In all cases, a strong correlation was observed between the theoretical results and those obtained practically, thereby enabling quantitative understanding and quantitative rules to be generated.