Eleven patients with severe largely irreversible obstructive airways disease and marked loss of exercise tolerance were submitted to a physical training programme. One patient died during the programme, and reasons are advanced for suggesting that the cause was unrelated. Nine of the 10 subjects who completed the course experienced considerable improvement in well-being and exercise tolerance, and demonstrable increase in physical working capacity. These changes were associated with increase in maximal oxygen uptake, reduction in minute-ventilation at submaximal work levels, and increase in maximum tolerated ventilatory volumes. I am grateful to Associate Professor Bryan Gandevia for his interest in the project and help in preparing this paper. I am indebted to the Director, Division of Establishments, Department of Public Health, for permission to publish. © 1968, British Medical Journal Publishing Group. All rights reserved.