Heart failure is common in patients with diabetes and about half of all patients with the syndrome of heart failure have preserved ejection fraction. The combination of heart failure and diabetes is an ominous sign and requires aggressive treatment. Heart failure treatments have improved the morbidity and mortality associated with heart failure dramatically over the past 20—30 years. We now review the basis for current medical therapies looking back over the important landmark trials which have led to the routine use of angiotensin converting enzyme inhibitors, β-blockers, aldosterone antagonists and others, concentrating particularly on the best therapies for patients with diabetes. Device therapy is also becoming more widespread and the recommendations are reviewed also. There are newer treatments emerging, such as fish oils and ivabradine, which may alter heart failure management in the future.