Circulation Journal Official Journal of the Japanese Circulation Society http://www. j-circ.or.jp atients with acute ST-segment elevation myocardial infarction (STEMI) require quick and efficient reperfusion treatment. The time from arrival at the hospital to percutaneous coronary intervention (PCI) for the infract-related artery, the so-called "door-to-balloon (D2B) time", is associated with the clinical outcome of patients. 1-7 Clinical practice guidelines recommend that STEMI patients receive primary PCI (PPCI) as soon as possible, and definitely within 90 min. 8-10 For the full realization of the benefits of PPCI in STEMI, an improved system needs to be established to decrease the total D2B time. In recent times, various innovations and key strategies have been shown to be associated with short D2B times. 11-14 Despite the implementation of such strategies, studies published hitherto, 15-17 except for a few, 18 indicate that only approximately 50% of STEMI patients receive PPCI within the recommended 90-min D2B time. Many patients do not receive prompt PPCI, and some of the institutions participating in the studies have shown that underuse of strategies is associated with longer D2B times. Several recent studies have examined the effectiveness of the formation of a D2B Alliance in reducing the D2B times to less than 90 min in STEMI. 19-21 Those studies have found marked changes in both the practice Background: Currently, the door-to-balloon (D2B) times observed in clinical practice in Taiwan are different from those recommended by evidence-based guidelines. D2B Alliance, a countrywide initiative for quality supported by the Taiwan Joint Commission on Hospital Accreditation, sought to achieve the goal of administering treatment to 75% of patients with ST-elevation myocardial infarction (STEMI) within 90 min of hospital presentation.