Angina and myocardial ischemia as detected by non-invasive modalities frequently occur in individuals without significant (obstructive) epicardial coronary artery disease. These are caused by microvascular coronary artery disease, coronary vasospasm, or a combination thereof. Patients suffering from these conditions have a poor quality of life, and prognosis, and frequently need rehospitalization which poses a significant burden on the healthcare system. It is now clear that the pathomechanism of these conditions can be objectively and quantitatively elucidated by invasive coronary thermodilution techniques and provocation tests. Recent publications and consensus documents have crystallized the diagnostic criteria of microvascular coronary artery disease and vasospastic angina. Systematic application of the diagnostic workup proposed by working groups makes it possible to identify individuals who benefit from medical therapies aimed at the pathomechanism thereby improving the quality of life of these patients. The present review summarizes the epidemiology, prognosis, and pathomechanism of microvascular coronary artery disease and vasospastic angina; provides a detailed, technical analysis of the invasive diagnostic modalities, the parameters of microvascular function applied in everyday practice, their background and caveats. The diagnostic aspects are complemented by pharmacologic approaches to treating these conditions available today and in the pipeline. Orv Hetil. 2024; 165(41): 1613–1620.