BACKGROUND: Clopidogrel prescription is a class I guideline recommendation for medically managed patients with non-ST-segment-elevation myocardial infarction (NSTEMI). However, clopidogrel has historically been underused in this population. We evaluated contemporary rates of its use and evaluated associated factors, with a particular focus on hospital quality of myocardial infarction (MI) care. METHODS AND RESULTS: We examined clopidogrel prescription rates among 23 186 patients with NSTEMI discharged from 382 US hospitals between October 2009 and March 2011. Associations between clopidogrel prescription and various patient and hospital factors, including hospital quality of MI care, were determined with regression modeling. Of the sample, 54.9% of eligible patients with NSTEMI received clopidogrel prescription at hospital discharge. Variation in rate by hospital was large, ranging from 22% to 97%. A variety of patient and hospital factors were associated with clopidogrel prescription. Hospital quality of MI care demonstrated modest association with clopidogrel prescription (odds ratio, 0.68; 95% CI, 0.54-0.85) between the lowest and highest hospital quality quartile) and accounted for 5.7% of the variation in prescription rates. CONCLUSIONS: Clopidogrel prescription is significantly underused in the medically managed NSTEMI population and demonstrates wide variability by hospital. Although hospital quality of MI care is associated with its use, the findings suggest that it only has a modest effect. Therefore, efforts to improve clopidogrel use likely will require measures beyond improving the overall hospital quality of MI care.