Wilson disease is an autosomal, recessive inherited disorder of copper metabolism, characterized by the accumulation of copper in the body due to defective biliary copper excretion of hepatocytes. Recently, novel components involved in copper metabolism, Wilson disease protein (ATP7B) and copper chaperones, have been identified. It has been demonstrated that ATP7B functions in copper secretion into the plasma, coupled with coeruloplasmin synthesis and biliary copper excretion. Genetic testing may help early diagnosis and with the beginning of therapy the development of symptoms can be prevented. Various mutations of ATP7B have been identified, the most common is in Hungary, the H1069Q mutation. Genetic screening should only be advised if there is a predominant mutation characteristic for the geographic area. The authors discuss the modern diagnostic and therapeutic possibilities of Wilson disease.