In my career as a purchasing professional, I had to resort to publications on Corporate Purchasing, but the ones I consulted did not address several important subjects. Hence the motivation to write The Ultimate Guide of Purchaser, with over 30,000 copies sold. Nevertheless, renewing the book is indispensable; several new topics are in this edition. Purchasing areas evolve quickly. Decades ago, tools were simple, with almost no electronic resources, and it took days to receive proposals. The focus was on Sales, without valuing Purchases, as if it were possible to survive without competitive costs! Organizational transformations, the reduction of structures, and the change of paradigms require different skills from purchasers to succeed. They participate in defining the purchasing strategy, develop tools to evaluate the supplier's performance, and are vital in implementing Strategic Sourcing and Global Sourcing, for example. When buying a good or service, the purchaser must assess the impact on other processes in the organization's production or operational chain. A company's profits depend on selling well and buying well. Knowing how to negotiate, purchase, and differentiate opportunities from pitfalls are skills that reduce costs and increase earnings. The Ultimate Guide of Purchaser analyzes industrial, service, and commercial acquisitions, and it is worth highlighting how the backbone of procurement procedures is similar in different branches. The book offers valuable insights and serves beginners and those with years in the field. The Ultimate Guide of Purchaser is also helpful for students to learn how to work in purchasing or logistics. Progressing in your career requires adapting to new challenges, and such a task is practically unfeasible without theoretical and practical support, and offering such resources is our modest intention. The development and updating of the book took years, aiming to provide qualified and beneficial information for you, reader!