The rapid growth of cancer cells, such as the case with pancreatic cancer cells, requires new blood vessel growth to sustain tumor viability. In fact, angiogenesis has been found to be closely correlated with rapid tumor growth and a poorer prognosis in pancreatic cancer. Pancreatic adenocarcinoma frequently has aberrant expression of several key regulators of angiogenesis and invasion. Via paracrine mechanisms, mutual stimulation between tumor cells and endothelial cells triggers tumor angiogenesis. In order for angiogenesis to continue, tumor cells or cells in its surrounding microenvironment must release stimulatory factors, while endothelial cells elicit a response which includes the release of proteolytic enzymes to degrade the extracellular matrix for migration and proliferation. Therefore, to extend our knowledge of the tumor microenvironment from our previous issue on the extracellular matrix, this Pancreatology and the Web article focuses on angiogenesis. and IAP.