Ion channels are the major class of membrane proteins responsible for rapid and regulated transport of ions across biological membranes and for the generation and propagation of electrical signals in the brain, heart, and skeletal and vascular tissues. Ion channels are also known to play critical roles in regulation of cell proliferation, insulin secretion and intracellular signaling in a variety of cell types. This book focuses on the roles of ion channels in vascular tissues under normal and pathological conditions. Vascular abnormalities are known to underlie a plethora of severe pathological conditions, such as atherosclerosis, systemic and pulmonary hypertension, coronary or cerebral vasospasm, and diabetes. In addition, misregulated angiogenesis is one of the major contributors to the development of tumors. Therefore, it is clearly imperative to obtain a better understanding of the molecular mechanisms that contribute to vascular disorders. This book will be the first comprehensive assembly of assays to present the studies that have been done during the last decade to elucidate the roles of ion channels in different vascular diseases.