Antimicrobial drugs are used in food animal production for several purposes: to treat a disease outbreak, to prevent disease, and to enhance feed efficiency and animal growth. While the technical benefits of antimicrobial use in animal production are well documented, there is a major lack of information on the economic impact on farmers’ incomes. This report reviews evidence on the economic benefits and costs of antimicrobials for the major animal producing species across several OECD countries as well as in Brazil and China. The findings indicate that the economic benefits are modest in modern farming systems where good production facilities, biosecurity measures, and management practices are in place. In large food animal producing countries such as Brazil, the use of antimicrobials is an important input to enhance the competitiveness of the industry. In China, the largest producer and user of antibiotics in animal production, antibiotics are often used as a substitute for less sanitary animal production facilities and the lack of appropriate biosecurity on the farm. This report concludes with several key policy options and practices, in particular those that induce farmers to place a greater emphasis on the economic benefits and costs of antimicrobials and alternative interventions in production in order to stem the rise in antimicrobial resistance.