Substantial progress has been made in our understanding of the biology of pancreatic cancer, and advances in patients' management have also taken place. Evidence is beginning to show that screening first-degree relatives of individuals with several family members affected by pancreatic cancer can identify non-invasive precursors of this malignant disease. The incidence of and number of deaths caused by pancreatic tumours have been gradually rising, even as incidence and mortality of other common cancers have been declining. Despite developments in detection and management of pancreatic cancer, only about 4% of patients will live 5 years after diagnosis. Survival is better for those with malignant disease localised to the pancreas, because surgical resection at present offers the only chance of cure. Unfortunately, 80–85% of patients present with advanced unresectable disease. Furthermore, pancreatic cancer responds poorly to most chemotherapeutic agents. Hence, we need to understand the biological mechanisms that contribute to development and progression of pancreatic tumours. In this Seminar we will discuss the most common and deadly form of pancreatic cancer, pancreatic ductal adenocarcinoma.