Depression in old age frequently follows a chronic and/or relapsing course, related to medical comorbidity, cognitive impairment and depletion of psychosocial resources. As endorsed by the US National Institutes of Health (NIH) Consensus Development Conference on the Diagnosis and Treatment of Late Life Depression, a major goal of treatment is to prevent relapse, recurrence and chronicity. We believe that most, if not all, elderly patients with major depressive episodes are appropriate candidates for maintenance therapy, because of the vulnerability to relapse and recurrence and because of the favourable benefit to risk ratio of available treatments. Antidepressant pharmacotherapy is the mainstay of this therapeutic goal, but psychosocial approaches (especially interpersonal psychotherapy) have also been shown to contribute significantly to prevention of a chronic depressive illness and to prevention of the disability that attends depression. Studies published to date have established the long term or maintenance efficacy of the tricyclic antidepressant nortriptyline. Current, ongoing studies are addressing the maintenance efficacy of paroxetine and citalopram to prolong recovery in depression associated with old age. These studies are focusing particularly on patients aged 70 years and above, who are at high risk of recurrence, and on patients in primary care settings, where under-recognition and under-treatment of depression in the elderly have been costly from a public health perspective in terms of increased medical utilisation, burden to patients and families, and high rates of suicide. Depression in old age is a major contributor to the global burden of illness-related disability, but it is extremely treatable if appropriate pharmacotherapy is prescribed and accepted by patients and their caregivers.