<p>An understanding of arterial, venous and lymphatic flow in the upper body in normal limbs and those at risk of, or with lymphoedema will greatly improve patient outcomes. However, there is much we do not know in this area, including the effects of compression upon lymphatic flow and drainage. Imaging and measuring capabilities are improving in this respect, but are often expensive and time-consuming. This, coupled with the unknown effects of individual, diurnal and seasonal variances on compression efficacy, means that future research should focus upon ways to monitor the pressure delivered by a garment, and its effects upon the fluids we are trying to control.</p>