Quantitative analysis of myocardial perfusion with SPECT and PET is a significant part of nuclear cardiology practice. Quantitative software can automatically segment the left ventricle, quantify left ventricular function, assess myocardial perfusion across individual vascular territories, and estimate changes in perfusion reserve upon exercise or pharmacologic stress. These mostly automated techniques provide high diagnostic accuracy for detecting obstructive coronary artery disease. Furthermore, with the increasing prevalence of myocardial injury from nonobstructive coronary disease and microvascular disease necessitates more nuanced methods to understand coronary flow dynamics dysfunction. Quantitative PET has emerged as a leading technique for evaluating coronary blood flow in all these settings. The objective of this chapter is to review the use of quantitative cardiac PET and discuss the latest developments in the field.