Before discussing the chronology of the general events in the Beef Hormones Issue we should differentiate between the naturally occurring hormones and the synthetic ones. Naturally occurring steroid hormones (estradiol, progesterone, and testosterone) are produced in significant quantities throughout the lifetime of every man, woman, and child, and required for the proper physiological functioning and maturation of every mammal. All endogenous steroid hormone products marketed in the U.S. for beef growth-promotion are formulated as implantable pellets and are designed to deliver the hormones at a slow, constant rate when injected subcutaneously under the skin of the animal’s ear. Numerous scientific studies have demonstrated that, when these drugs are used in accordance with their approved conditions of use, concentrations of the hormones in edible tissues remain within the normal physiological range that has been established for untreated animals of the same age and sex. Because of the slow release of very small amounts of the hormone and a short average half-life (approximately 10 minutes), it has been determined that no pre-slaughter withdrawal time is necessary to protect the public health. Consumers are not at risk from eating food from animals treated with these compounds because the amount of added hormone is negligible compared to the amount normally found in the edible tissues of untreated animals and that is naturally produced by the consumer’s own body.