The historical background for the use of alternate suction and pressure in the treatment of vascular disease has been reviewed by Herrmann and Reid.1In spite of the fact that such treatment is a century and a quarter old, a great deal of credit is due to Landis and Gibbon2and to Reid and Herrmann3for reviving it, for perfecting the mechanism by which it is applied, and for testing the value of the treatment both physiologically and clinically. Herrmann and Reid4have proposed the name "pavaex" for this treatment, the term signifying passive vascular exercise, and the changes in pressure being gradual. Landis5has retained the denotation "alternate pressure and suction," the changes in pressure being sudden. At the clinic, we have used the unit devised by Herrmann and Reid since February 1934. In the present paper we attempt to evaluate this therapeutic procedure