Laws governing pharmacy practice in the United States date back to colonial times. However, laws and regulations at the federal level did not appear until the early twentieth century. The Food, Drug, and Cosmetic Act, originally passed in 1938, is the core piece of federal legislation that governs drugs, biologics, and medical devices. Since its passage, additional amendments and laws have been enacted that modify, add to, or remove from the Act’s provisions. Additionally, the Food, Drug, and Cosmetic Act provides the Food and Drug Administration the authority to regulate drugs, biologics, and devices, and to develop and enforce rules and regulations that further govern therapeutic safety and efficacy in our country. Additional laws unrelated to the Food, Drug, and Cosmetic Act have also been passed over the years in an effort to further ensure safe use of drugs and other products. Federal law and regulation primarily apply to products involved in interstate commerce. State law and regulation governs pharmacy practice on a more operational level. On common subjects, federal and state law generally concur. When there is a difference, the pharmacist should always abide by the stricter requirement.