INTRODUCTION: Dyslipidaemia is a major risk factor for coronary heart disease (CHD). There is a lack of data on the extent of lipid abnormalities and lipid-lowering therapy (LLT) in Singapore. METHODS: The Dyslipidemia International Study (DYSIS) II was a multinational observational study of patients with stable CHD and hospitalised patients with an acute coronary syndrome (ACS). A full lipid profile and use of LLT were documented at baseline, and for the ACS cohort, at four months post-hospitalisation. RESULTS: 325 patients were recruited from four sites in Singapore; 199 had stable CHD and 126 were hospitalised with an ACS. At baseline, 96.5% of the CHD cohort and 66.4% of the ACS cohort were being treated with LLT. In both cohorts, low-density lipoprotein cholesterol (LDL-C) levels were lower for the treated than the non-treated patients; accordingly, a higher proportion of patients met the LDL-C goal of < 70 mg/dL (CHD: 28.1% vs. 0%, p = 0.10; ACS: 20.2% vs. 0%, p < 0.01). By the four-month follow-up, a higher proportion of the ACS patients that were originally not treated with LLT had met the LDL-C goal (from 0% to 54.5%), correlating with the increased use of medication. However, there was negligible improvement in the patients who were treated prior to the ACS. CONCLUSION Dyslipidaemia is a significant concern in Singapore, with few patients with stable or acute CHD meeting the recommended European Society of Cardiology/European Atherosclerosis Society goal. LLT was widely used but not optimised, indicating considerable scope for improved management of these very-high-risk patients.