A survey was undertaken about bacteriologic, epidemiologic and clinical features of infections caused by Yersinia. Yersinia enterocolitica and Yersinia pseudotuberculosis are gram negative rods of the enterobacteriaceae family. The number of cases of these infections has increased considerably in the past few years. Erythema nodosum often occurs after an enteritic infection by Yersinia. Other skin manifestations are erythema exsudativum multiforme, erythema figuratum and "drug-eruption-like exanthema". Moreover, Yersinia-arthritis may occur. In one particular case a Reiter-syndrome was described. The mechanism whereby Yersinia induce skin lesions is unknown. Prognosis is good. Therapy of choice for infections caused by Yersinia are tetracyclines.