Modern intensive treatment modalities have led to an increasing number of survivors of childhood cancer, who are at risk for developing long-term sequelae. Since decline of renal function can develop subclinically, adequate surveillance is required for survivors previously treated with nephrotoxic treatment modalities. We describe a 34-year-old man, who had been treated for nephroblastoma (stage I) at the age of 5 years and who regularly visited the adult late-effects clinic for survivors of childhood cancer. Twenty years after his treatment for nephroblastoma glomerular function started to decline and progressive chronic kidney disease (CKD) stage 3 developed. It is important to recognise that survivors of childhood cancer can be at risk of developing long-term effects, including impaired renal function. Apart from regular surveillance by expert medical specialists dedicated to childhood cancer survivor care, more intensive communication with primary health care physicians is necessary to improve awareness of these issues in the growing cohort of childhood cancer survivors.