The book "Mg2+ and Excitable Membranes" is the result of a symposium that took place in 1989 during the 12th annual meeting of the European Neuroscience Association in Turin. It brings together leading experts from around the world to discuss the physiological and clinical effects of magnesium on excitable cells. Magnesium ions play a crucial role in regulating various cellular functions and are associated with the control of neuronal excitability as well as cardiovascular diseases. In recent years, new electrophysiological techniques have provided important insights into the modulatory effects of magnesium on ion channels and neurotransmitter receptor proteins. The book offers a comprehensive analysis of the mechanisms by which magnesium influences ion passage through channels and highlights the significance of magnesium in synaptic transmission, brain aging, and cardiac activity.