In future update of clinical guidelines on dialysis adequacy prepared by the International Society of Nephrology, the main priorities are given to four topics: the choice of dialysis modality, conditions at dialysis start, vascular access, adequacy of hemodialysis with an emphasis on correction of water balance and dialysis duration. In Europe negative scenarios for the development of these problems have been avoided: the choice of dialysis modality is more available; neither early nor late start is widespread; vascular access is always held in attention; dialysis shorter than four hours is not used, and instrumental hydration assessments are being actively developed. New approaches to the intensifi cation of dialysis, fi rst of all with regard to the elimination of more and more high-molecular substances related to uremic toxins are used. The limiting factor for an increase in permeability of new membranes is the necessity to exclude (at least minimize) the albumin loss. To meet these requirements, the membrane must have a high retention onset (substances with a lower molecular weight are retained by less than 10%) and a medium cut-off (less than 10% of a substance with a higher molecular weight is lost through the membrane). Such membranes effectively remove substances with molecular weight of up to 50 kD, but as reliably as conventional high-fl ux membranes, eliminate substantial losses of albumin. Fundamentally important is that such membrane permeability provides throughout the dialyzer length the internal fi ltration, and then back fi ltration (equivalent to the replacement solution) with a convection volume of about half that of hemodiafi ltration with conventional dialysis machines and without a separate system for preparing and introducing the replacement solution. Thereby, the risks of thrombosis of the system and a decrease in the diffusive clearance due to the hemoconcentration in the output part of the dialyzer and the circuit before infusion of replacement solution is reduced. The fi rst clinical evidence confi rmed the effi cacy and safety of such a solution defi ned as expander dialysis.