Double J (DJ)stents are a comfortable method for assuring urine passage with little or no burden for the patient. However, the lack of or minimal impairment of physical activity has the disadvantage that an inserted DJ stent can be "forgotten". In cases of encrustation, stent removal can be impossible or a stent can tear off. To remove encrusted stents all modern, minimally invasive endourological techniques are used. In rare cases, surgical procedures are essential. To avoid these difficulties, patients with DJ stents have to be closely checked to recognize the beginning of encrustation as early as possible. The removal of DJ stents should be carried out as early as possible in patients for whom they are required only short-term.