Chronic pancreatitis is in advanced European and North American countries the statistically most important source of morbidity and mortality among benign pancreatopathies. It is defined as affection of the pancreas by chronic inflammation whereby the secretory parenchyma is gradually replaced by fibrous tissue. The fibrosis is irreversible and the disease has a progressing trend. In advanced countries the main pathogenetic factor has been for some centuries alcohol consumption. Chronic pancreatitis can be classified with regard to its morphology, etiology or pathogenesis. Most frequently the classification of chronic pancreatitis with regard to morphological changes is used, whereby the latter are based on different pathogenetic mechanisms. The present Marseille-Rome classification is valid from 1988 and divides chronic pancreatitis according to morphological changes into three groups. 1. Chronic calcifying pancreatitis. 2. Obstructive chronic pancreatitis. 3. Primarily inflammatory chronic pancreatitis. In some publications pancreatic fibrosis is listed as a special category. The submitted paper gives an up to date picture of chronic pancreatitis from the aspect of etiopathogenesis, it draws attention to the weak points of the contemporary classification and provides information on the genetic diagnosis of some rare forms of this highly prevalent disease.