Physiotherapists are involved in the management of patients with critical illness. Physiotherapy assessment is focused on physical deconditioning and related problems (muscle weakness, joint stiffness, impaired functional exercise capacity, physical inactivity) and respiratory conditions (retained airway secretions, atelectasis and respiratory muscle weakness) to identify targets for physiotherapy. Evidence-based targets for physiotherapy are deconditioning, impaired airway clearance, atelectasis, (re-)intubation avoidance and weaning failure. Early physical activity and mobilisation are essential in the prevention, attenuation or reversion of physical deconditioning related to critical illness. A variety of modalities for exercise training and early mobility are evidence-based and must be implemented depending on the stage of critical illness, co-morbid conditions and cooperation of the patient. The physiotherapist should be responsible for implementing mobilization plans and exercise prescription and make recommendations for progression of these plans, jointly with medical and nursing staff. © 2011, Nederlandse Vereniging voor Intensive Care. All Rights Reserved.