Diabetes (DM) adversely affects prognosis in acute coronary syndromes (ACS). Guidelines promote optimal glycemic management. Cardiac care often occurs in subspecialty units where DM care might not be a primary focus. A questionnaire was circulated to 1183 cardiologists (CARDs), endocrinologists (ENDOs), and internists between February and May 2012 to determine current practices of DM management in patients presenting with ACS. The response rate was 14%. ENDOs differed in perception of DM frequency compared with CARDs and the availability of ENDO consultation within 24 hours and on routinely-ordered tests. Disparity also existed in who was believed to be primarily responsible for in-hospital DM care in ACS: ENDOs perceived they managed glycemia more often than CARDs believed they did. CARDs indicated they most often managed DM after discharge and ENDOs said this occurred much less. However, CARDs reported ENDOs were the best health care professional to follow patients after discharge. ENDOs had higher comfort initiating and titrating oral hypoglycemic agents or various insulin regimens. There was also no difference in these specialists' perceptions that optimizing glucose levels during the acute phase and in the long-term improves cardiovascular outcomes. Significant differences exist in the perception of the magnitude of the problem, acute and longer-term process of care, and comfort initiating new therapies. Nevertheless, all practitioners agree that optimal DM care affects short- and long-term outcomes of patients. Better systems of care are required to optimally manage ACS patients with DM during admission and after discharge from cardiology services.