Plethysmography using strain gauge photo cell or air techniques and Doppler have been well established non-invasive testing modalities in the evaluation of vascular disease for a number of years. With the advances in ultrasound the need for plethysmography has decreased dramatically. Plethysmography is not as accurate as duplex scanning and is very operator dependent. However, we still employ the use of PPG routinely particularly in the evaluation of impotence, suspected thoracic outlet syndrome, digital ischaemia and Raynaud’s syndrome.