Coronary artery disease is the most prevalent manifestation of cardiovascular disease and acute coronary syndromes (ACS) are one of the potentially life-threatening presentations of coronary artery disease. Only 10–30% of patients with chest pain are clearly defined as having ACS based on history, electrocardiogram and serial serum biomarkers [1,2]. One of the most difficult challenges in cardiology is determining whether chest pain is cardiovascular in origin. Imaging in ACS plays an important role in both diagnosis and assessment of the long-term prognosis following the event. Echocardiography, single photon emission computed tomography (SPECT), multidetector computed tomography (MDCT), and cardiac magnetic resonance (CMR) have all been demonstrated to have favorable diagnostic and in some cases prognostic value in the setting of chest pain. Each of these techniques interrogate different stages of the ischemic cascade (Figure 8.1). In this chapter, we will discuss the role of different imaging techniques in the evaluation of ACS.