Within the project “Advanced Processes for Hybrid Metal/Plastic Products” which is part of the Cluster of Excellence “Integrative Production Technology for High-Wage Countries”, established and financed by the German Research Foundation (DFG), new hybrid processes for the production of metal/plastic-composites will be developed. The activities of the Foundry Institute focus on the processing of structural parts with excellent mechanical properties and special integrated functions by combining two original mould operations. In the long term, the metal/plastic-composites are to be produced in a single step process, using one mould and one machine. Beside the combination of the two processes, high pressure die casting and injection moulding, preliminary test geometries will be manufactured in separate moulds. The operation using the two moulds consists in the production of the aluminium metal part in a pressure die casting mould, and subsequently the injection of the plastic component into an injection mould. The basics needed to define the adhesion mechanism between metal and plastic were investigated under experimental conditions in order to determine appropriate results for tests, carried out under the process conditions of high pressure die casting. It is proposed to find and to develop new concepts to join these two different materials. The best bonding mechanism will be chosen to obtain the first metal/plastic hybrid products in the so-called One-Step-Process. A selection of promising results concerning the bond strength of different joining concepts under application terms are presented in this paper.