This article compares the use of chemical and biological amendments in shrimp farming in Asia and the Americas. The information comes mainly from the author’s experience in Thailand and Ecuador, as well as from the literature. The amendments are discussed according to three major categories: (1) water and soil quality management products, (2) biocides, and (3) feed additives. Certain agents, while necessary to successful shrimp farming, should be used only when needed and in a safe and responsible manner.