1 . A technique for measuring venous pressure during exercise is described.

2. The findings in normal and abnormal conditions of the lower limb are recorded.

3. The mechanisms involved in the return of blood from the lower limb in various conditions are discussed, with particular reference to the post-phlebitic state.

4. The need for an objective method of assessing the results of surgical treatment of venous abnormalities in the lower limb is stressed.