Patients with chronic kidney disease (CKD) are inactive and have reduced physical functioning and performance. Aerobic exercise interventions have been shown to increase maximal oxygen consumption in selected patients. In addition, preliminary evidence, although mixed, suggests that aerobic exercise training can improve blood pressure control, lipid profiles and mental health in this population. A few larger studies are now available showing that aerobic training can also improve physical functioning and performance. The impact on survival or hospitalisation has not been determined. Resistance exercise training, although less studied, appears to increase muscle strength and size and may also improve functioning. There have been several reports of successful combined exercise interventions, but the designs have not allowed evaluation of the relative benefits of aerobic and resistance training on physical functioning. Despite the evidence that exercise is safe and beneficial in patients with CKD, dialysis patients remain inactive, and exercise assessment, counselling and training is not widely offered to patients with CKD. Studies of the barriers to patient participation in exercise and to provider assessment and recommendations are needed so that more widely generalisable interventions can be developed. However, in the interim, patients should be encouraged to participate in moderate physical activity to meet the US Surgeon General's recommendations. Patients who are weak can benefit from strength-training interventions. Resistance and aerobic exercise programmes should be initiated at relatively low intensity in patients with CKD and progressed as slowly as tolerated in order to avoid injury and discontinuation of exercise. For patients on haemodialysis, incorporation of exercise into the dialysis session may increase patient participation and tolerance of exercise.