Despite the widespread dissemination of information concerning the negative health consequences associated with sedentary living, adult physical activity in many industrialised nations remains well below recommended levels. Approximately 50% of individuals who start an aerobic exercise programme will stop within the first 6 months, even though it is well known that to obtain the health benefits associated with physical activity, participation must be maintained. Programmes involving the use of behaviour management techniques appear to increase short term adherence to exercise. Recently, an adherence rate of greater than 95% over 6 months was achieved in a large group of university employees who participated in aerobic training using a ‘behavioural treatment packages’ approach. Unfortunately, inconsistencies in the literature on definitions and measurement of adherence make valid comparisons among studies difficult. Also, long term follow-up of behavioural intervention methods and their effect on exercise adherence is generally lacking. It is likely that strategies to increase physical activity participation in the general population will demand multiple levels of intervention (personal, organisational, environmental and societal) if they are to succeed in the long term.