The growing interest in a personalized choice of dialysate calcium concentration faces some important unsolved questions. First, the desired aims to be achieved should be clarified, as different d-Ca concentrations might differentially impact dialysis calcium balance and serum calcium concentration. A second point to be addressed is how to achieve the desired goals; the kinetics of calcium during dialysis treatment are complex. This is not an easy task and probably only an automatic device able to read serum calcium concentration in real-time and adjust d-Ca to it might supply an effective method for individualizing d-Ca. Finally, it is not even clear whether individualizing d-Ca is worth doing; cost-effectiveness studies might give some further insights into this intricate issue.