Objective-The aim of the present study was to describe how the diagnosis of heart failure (HF) was assessed, aetiology and management in elderly patients with non-insulin-dependent diabetes mellitus (NIDDM) in primary health care, with special reference to use of echocardiography. Design-Descriptive retrospective investigation. Setting-Ronneby and Karlskrona communities, both situated on the Swedish south-east coast, 28,600 and 60,600 inhabitants, respectively. Patients-279 patients with NIDDM, mean age 77 years (range 70-85). Main outcome measures-Prevalence, aetiology, diagnostic procedures and management of HF. Results-The majority of patients were given the diagnosis of HF mainly as a result of clinical examination, ECG and chest X-ray, or of hospitalisation for HF. The diagnosis of HF by the primary care physicians was based on an objective evaluation of cardiac function in 8% of the patients. Hypertension was the predominant associated disease, followed by ischaemic heart disease (IHD). Therapy included diuretics (91%), angiotensin-converting enzyme (ACE) inhibitors (43%) and digoxin (53%). Conclusion-There is still a gap between current management of HF in primary care and guidelines, particularly in the case of diagnosis that is not generally based on an objective evaluation of cardiac function.