Injuries resulting from falls are a significant public health issue, particularly for older people. This review provides an update of the evidence on the effects of various physical activity (PA) or exercise intervention strategies for the prevention of unintentional falls among older people. Six systematic reviews, and three randomised controlled trials not incorporated in previous reviews, were located with a literature search. There is clear evidence that a targeted supervised home exercise program of strength and balance exercise and walking practice, prescribed by a trained health professional, can prevent falls among older community dwellers. There is also an indication that untargeted group exercise (ie, not individually prescribed) can prevent falls among community dwellers, particularly if it involves Tai Chi or other exercises which challenge balance. There is some indication that individual prescription of PA is more important in frailer groups. Further investigation is required to establish the effects of PA in residential aged care, and the relative effects of different types of PA in different populations. In addition, multidisciplinary, multifactorial. health/environmental risk factor screening/intervention programs have been found to be effective in preventing falls. For many individuals with physical risk factors for falls (eg, impaired strength, balance or functional ability), PA alone is likely to reduce the risk of falls. For those with additional risk factors (eg, visual impairments, psychoactive medication use), other interventions may also be required.