This thesis deals with the development of a specification regarding a push-button, which will be used to control the gear-shifting function in an automobile. In addition to this the author will describe different techniques and theories that have been helpful in achieving data and results for the specification.Kongsberg Automotive AB, is located in Mullsjö, Sweden, the company supplies parts to the automotive industry. In the research and development department, R&D, there is a group that works with development of Shift-By-Wire systems. In an automobile with a Shift-By-Wire system the communication between the gear-shifter and the gear-box occurs electronically. The mechanical link is, in most cases, taken away and replaced by the digital system.