This paper provides an overview about the consequences of a 14/42 V - Electrical Power Supply System for the Electrical Interconnection and Switching Technology.It presents design guidelines and solutions for connector systems including advanced applications like fuse and relay boxes and gives an overview of those existing connectors already suited for 42 V and even higher voltages. The problem of arcing due to the increased voltage is discussed for the case that mating and unmating under load has to be taken into consideration.Arcing also has a tremendous impact on the design of 42 V proof relays. Therefore, some basic results be presented along with proposals how these problems can be overcome by appropriate designs.Another part of the paper looks at the electrical power supply system itself. Here interconnection techniques for new battery systems are discussed.Finally, the chances for new technologies are highlighted. Among others the development of connectors with integrated electronics and the replacement of round cables by flex foil solutions will be presented.