In the modern world, cognitive ability is required increasingly. Particularly in elderly employees this can result in cognitive overload when work demands exceed cognitive abilities. International studies have shown that general cognitive ageing can not be assumed, but that different cognitive functions change differently with age. Cognitive functions remain stable until old age in many elderly people, whereas other abilities (working memory, executive control functions) deteriorate with increasing age. The plasticity of the human brain enables individuals approaching the end of their working lives to compensate cognitive deficits and losses. This makes up for performance deficits and allows the maintenance of a stable functional state. Compensation processes in the ageing brain, their impact on the cognitive abilities necessary to perform tasks and the “physiological costs” involved can be analysed by means of psychophysiological methods. Behavioural data (e.g. reaction time, error ratio), psychophysiological parameters (e.g. bioelectrical brain activity and vegetative parameters) can be analysed and used to estimate the impact on well-being and health. In the present paper we have summarized recent data for age-related cognitive changes and for common compensatory mechanisms. We present psychophysiological approaches for assessing these compensatory mechanisms at the neurological and vegetative levels. These can reveal risk factors for age-related cognitive decline and suggest preventive strategies which aim to maintain the cognitive performance level and health of elderly employees.