Age-related changes, for example reduced elasticity and earlier airways collapse, predispose the elderly to respiratory infection. Other factors such as a lifetime of smoking, the use of hypnotics, or the development of stroke also predispose. Pneumonia becomes increasingly common with advancing age, and both morbidity and mortality increase with associated disease burden. Diagnosis of pneumonia may be more difficult in the aged because of physiological changes. However, careful physical examination with accurate, regular recording of body temperature will usually reveal the characteristic features of pneumonia, which should be confirmed by chest radiograph. In the frail elderly, the onset of impaired function, such as confusion, immobility, falling or incontinence, should raise suspicion of infection. Pneumonia is classified as community-acquired, nursing home-acquired or nosocomial, which helps in the empirical choice of antibiotics. Streptococcus pneumoniae is the most common organism in the community, then Haemophilus influenzae and Branhamella catarrhalis. Gram-negative organisms like Klebsiella and Escherichia coli are more common in nosocomial infections. Nursing home patients with pneumonia tend to be more frail than those in the community. Treatment is directed at eradication of the organism with the appropriate antibiotic, maintaining hydration and oxygenation, as well as managing impaired mobility, faecal loading, urinary incontinence and confusion. Influenza vaccination is strongly recommended for the frail elderly. Tuberculosis remains an important diagnosis in the frail elderly and should always be considered, especially in patients with respiratory infection who fail to respond to conventional therapy.