Aim: To explore the importance of factors influencing the end-of-life care decision making of health care professionals (HCPs) in Singapore. Methods: This cross-sectional survey encompassed facets of patient, family, and HCP-related care considerations. In total, 187 questionnaires were distributed to physicians and nurses and had a response rate of 78.6%. Results: The respondents rated patients’ wishes (96.6%), their clinical symptoms (93.9%), and patients’ beliefs (91.1%) very high. In all, 94.6% of the HCPs would respect a competent patient’s wishes over the family’s wishes when goals conflict. However, 59.9% of HCPs would abide by the family’s wishes when the patient loses capacity even if the patient’s previously expressed wishes are known. Conclusion: End-of-life care decision making by HCPs appears largely patient centered, although familial determination still wields significant influence with implications for advance care planning.