Fibroinflammatory changes to the pancreatic tissue characterize chronic pancreatitis. This article summarizes the current state of knowledge on the pathology and pathogenesis of chronic pancreatitis associated with alcohol, hereditary factors, metabolic conditions, and anatomical abnormalities. Specifically, the pathogenetic mechanisms that lead to chronic pancreatitis in patients with alcohol abuse will be discussed. In addition, brief descriptions of the features of chronic pancreatitis of nonalcoholic origin and of the pancreatic fibrosis that is not associated with symptoms of chronic pancreatitis will be given.