Five hundred consecutive cardiological patients were reviewed and evaluated by echocardiography in Mulago Hospital as a referral service. All diagnostic problems in cardiology in the hospital and to a certain degree from other institutions were reviewed. The commonest diagnosis was endomyocardial fibrosis (EMF) 19.8%, followed by congenital heart disease (CHD) 15% and rheumatic heart disease (RHD) 11%. The anatomical distribution of fibrotic lesions in EMF (left, right or biventricular) correlated with that found in previous autopsy series from Mulago Hospital thus demonstrating the accuracy of echocardiography. We were able to quantify the contribution of echocardiography to a correct diagnosis which varied between 13% in RHD to 90% in mitral valve prolapse (MVP). Echocardiography was able to confirm the clinical diagnosis of subacute bacterial endocarditis (SBE) in 69% of cases. The obtained data suggests that EMF may be the most common heart disease in Uganda contrary to the pattern of heart disease outlined in earlier works. The favourable cost/benefit ratio of echocardiography (i.e. its easy availability and maintenance), as well as the absence of consumable materials in comparison to other cardiac diagnostic tools such as catheterization, chest X-ray and ECG is emphasized, together with the multipurpose use of the machine.