1. The Hendon motor and the Hendon valve are described.

1. A series of patients with respiratory paralysis after anterior poliomyelitis is reported.

2. The examination routine is described and its value discussed.

3. Details are given of methods of respiratory rehabilitation and of the various pitfalls encountered, with suggestions for their avoidance.

4. The rates of recovery of vital capacity (and percentage of the expected vital capacity) in adults and children are analysed and compared with the rates given by Sharrard for nonrespiratory individual muscles in treated patients. It is shown that during the first year treated patients tend to recover approximately 3 to 4 per cent of their expected vital capacity per month rather than to regain any definite proportion of their current vital capacity.