The pancreatic duct cell, although a minor cell type of the pancreas, plays an important role in fluid/electrolyte and mucin secretion, and has been implicated in the development of pancreatic cancer, alcoholic pancreatitis, and cystic fibrosis. In the normal pancreas, the duct cell has the same low proliferative rate as acinar and endocrine cells. Under certain pathological circumstances, duct cells, as well as acinar and islet cells, may be stimulated to proliferate more rapidly. Pancreatic duct cells exhibit certain features not shared by acinar and/or endocrine cells, including a variety of antigens, mucins, enzymes, and morphological features. Adult duct cells resemble fetal pancreatic duct-like cells morphologically, but they have differentiated to at least a limited extent from their precursor cell type. Although there is no evidence that duct cells differentiate into acinar cells after pancreatic morphogenesis is complete, some islet cells develop from duct epithelium in the early postnatal period. Some pathological conditions may lead to the postnatal formation of islet cells from duct cells and may cause acinar cells to become duct-like in morphology or to die and be replaced by duct cells. A better understanding of duct cells is now possible because of the development of techniques for their isolation and culture free from other cell types. Several such techniques are reviewed.