Heart failure is a common and often debilitating condition, but one for which there exists a variety of effective pharmacological therapies. The angiotensin converting enzyme (ACE) inhibitors represent one of the mainstays of the treatment of heart failure. In spite of a wealth of evidence regarding the efficacy of these agents in improving mortality and morbidity in heart failure, they are often under-utilised. Failure to prescribe or to prematurely withdraw ACE inhibitor therapy often stems from physicians perceptions regarding the likelihood of unwanted effects, in particular hypotension, renal impairment and cough. The evidence from clinical trials is that these unwanted effects are relatively uncommon. In routine clinical practice the rate of prescription of ACE inhibitor therapy is related to the expertise and motivation of the physician. There is a need for education of all health care professionals involved in the care of patients with heart failure with regard to the maximisation of ACE inhibitor therapy in heart failure.