Recent studies have highlighted that dyspneic patients comprise a high-risk subgroup of patients referred for cardiac stress testing. Even after adjusting for the presence and degree of coronary artery disease the risk of cardiac and all-cause mortality is at least three- to fivefold higher in dyspneic patients compared to asymptomatic or those with chest pain. Stress echocardiography is uniquely positioned to characterize all potential cardiovascular etiologies of dyspnea from global and regional systolic dysfunction, myocardial ischemia to valvular heart disease, pulmonary hypertension and diastolic dysfunction. Various data point to diastolic dysfunction and associated heart failure as the major potential etiology for dyspnea as well as the likely cause of the heightened mortality risk. Doppler echocardiography at rest and with stress can now characterize the hemodynamics of diastolic dysfunction and close the loop on the comprehensive assessment of the patient who has exertional shortness of breath. This review discusses the role of the Doppler echocardiographic diastolic stress test in the evaluation of patients with cardiac dyspnea.