Population-based study demonstrated that iron deficiency is really frequent, and anaemia not rare. Nevertheless, iron deficiency afflicts anaemic patients at all stages of chronic kidney disease (CKD). Bioavailability of oral iron supplements is highly variable, particularly in case of CKD. Moreover, efficacy is in favour of intravenous (i.v.) iron over oral iron. And safety of i.v. iron sucrose is today definite. Finally, recommended targets, i.e. Hb > 11 g/dl and transferring saturation > 20%, necessitate i.v. iron.