The staphylococcal enterotoxins, produced primarily by Staphylococcus aureus, are a group of closely related single polypeptide chains with molecular weights of 26–29 kDa. They can be differentiated into seven distinct types on the basis of their serological activity, although they all possess similar biological functions. In addition to their ability to cause staphylococcal food poisoning, the staphylococcal enterotoxins have been implicated in other forms of staphylococcal disease, including enteritis and toxic shock syndrome. This may be due wholly or, in part, to the interaction of these toxins with components of the immune system in a manner that results in several of the symptoms observed in staphylococcal disease. This article reviews the significance of staphylococcal enterotoxins in disease and includes aspects of their biological activities together with methods for their detection in food and clinical samples.