In purchasing lies the profit - this well-known merchant's adage is based on the fact that reducing material costs can significantly impact a company's operating results. In times when companies face intense competition, costs are more critical than ever. The share of material costs represents the largest controllable cost block in many companies. This is particularly evident in businesses where value creation is largely realized through external partners due to a reduction in production depth. Therefore, purchasing plays a strategically significant role. This book analyzes the influence of purchasing on a company's operating results and emphasizes that success in purchasing can be achieved through the use of a performance measurement system. It examines purchasing metrics and evaluates their practical applicability. As a result, the reader receives a performance measurement system capable of making a substantial contribution to the long-term success of the company.