The authors present the role of the Ergonovine test in establishing the diagnosis of the angina produced by coronary spasm. ECG alterations induced by Ergonovine, like transparietal ischemia (monophasic wave) or subendocardic ischemia, not only make possible a correct diagnosis, but they also underline the mechanism of angina and the therapeutical measures. Severe arrhythmias and the danger of sudden death are the two elements illustrating the importance of this coronary spastic mechanism. Nitroglycerine, isosorbidinitrate and calcium antagonists are the drugs of election for the prevention and also for the treatment of coronary spasm.