In 2000, the European Society of Cardiology and American College of Cardiology issued a consensus document concerning the redefinition of myocardial infarction (MI). They proposed that the diagnosis of acute MI should be based on the rise and fall of specific markers combined with at least one of the following: ischaemic symptoms, ECG changes consistent with ischaemia or infarction, or coronary intervention. The implications of this redefinition are widespread, and it has been met with mixed opinions from physicians. Here we present the results of a survey, sent to 1,000 consultants in cardiology and general medicine, concerning the availability and their use of cardiac markers and their current working diagnosis of MI. Four case studies were included in the survey. Some 361 responses were analysed. Creatine kinase (CK) remains the most frequently used marker for the diagnosis of MI, but 23% of consultants had moved to a definition based on troponins. Fourteen per cent of consultants no longer used CK in their practice. Ninety-two per cent of consultants had access to troponin assays. Definitions varied widely between consultants, even within individual hospitals, as did the responses to the case studies.