Despite the use of high permeable dialyzers, which combine diffusive with convective clearance, the clinical outcome of hemodialysis (HD) patients remains poor. In post-dilution online hemodiafiltration (denoted further on as HDF) diffusive clearance is similar to HD, while the amount of convective transport is considerable increased. Recently, 4 randomized controlled trails have been published which compared HD with HDF. Although the results of the individual studies were inconclusive, a recent meta-analysis, using individual patient data of these studies, showed a superior outcome for patients treated with HDF. The largest mortality reduction was obtained in patients receiving the highest convection volume (high-volume HDF [HV-HDF] >23 L/1.73 m2/session): all-cause mortality [22% (95 % confidence interval [CI] 2-38)], cardiovascular disease (CVD) mortality [31% (95 % CI 0-53)].