Acute coronary syndrome (ACS) is associated with both short- and long-term unfavorable prognosis. Therefore, medical societies developed risk scores for predicting mortality and assessing decision-making regarding early aggressive treatment in patients presenting an ACS. The Thrombolysis In Myocardial Infarction and the Global Registry of Acute Coronary Events risk scores are the most extensively investigated scores for ACS. Clinical judgment is also important. Significant differences in aggressive treatment of ACS still exist with respect to gender, age, and ethnicity. The reasons for these discrepancies need to be further elucidated in future studies. Therefore, generalizability of stratifications and risk scores in certain populations should be performed with caution.