There is a continued need for therapies to improve respiratory function and quality of life in patients with amyotrophic lateral sclerosis. In this pilot trial, we studied 8 subjects with amyotrophic lateral sclerosis and respiratory involvement. We measured respiratory function and quality of life at baseline. We then taught subjects diaphragm training, a method of breath control designed to improve respiratory muscle strength and efficiency. We repeated measures of respiratory function and quality of life 6 and 12 weeks later. There was no significant improvement in any outcome measure after instituting diaphragm training. There was a nonsignificant trend toward a slower rate of decline in respiratory function in those subjects who mastered the technique; however, only half the subjects were able to successfully change their pattern of breathing. A larger study of this technique is warranted; however, in determining the sample size for a larger study, the difficulty for patients in mastering the technique must be taken into consideration.