One of the most distinguishing features for companies today is that they must have a close collaboration and keep up a good relationship with their suppliers. This is important for the companies chance of survival and for them to compete in their markets. This essay will discuss the subject of Scania’s long-term collaboration with their suppliers. The purpose of the essay in this case study is to analyze if a long-term cooperation with a supplier is of essence upon renegotiations of continued collaboration. The hypothesis is: What effects do a long-term collaboration with suppliers have for decreased production costs with maintained quality, within the vehicle industry?The empirical survey has been made in the form of a case study of Scania and two of their suppliers, WABCO and PlaCell. In the theoretical part, a number of logistics theories have been examined, among others the ”value star”. The theories have then been compared with the empirical survey.The survey shows that Scania, WABCO and PlaCell make good effort to keep up and strengthen their relationships amongst each other. Among other things, theme days are organised between the companies to strenghten the relationships. Both WABCO and PlaCell are important to Scania. WABCO is a development supplier, which produces a very complex breaking system. PlaCell is a contract supplier of injection moulding, which is an easier product to find alternative suppliers for.The result will show that the significance of the suppliers is very important, according to Scania. Scania spend a lot of time and resources to find clever and reliable suppliers, but it is not guaranteed that the cooperation will continue. The investigations in this essay will show that these collaborations are of large importance to Scania with regards to lower production costs with quality maintained. Long term cooperation can help to and maintain a good quality. This together with a sound and continuous competitive situation where every product/function are manufactured by the right supplier gives, according to Scania, the best total cost.