The detection of potentially highly curable low-grade bladder cancers by noninvasive techniques remains an unsolved problem. Conventional cytology detects such tumors with 50% sensitivity, the addition of DNA image analysis cytometry in patients with previous transitional cell superficial bladder carcinoma increases the chance to detect low-grade tumors. The specificity and sensitivity of detection of low-grade bladder tumors can be further improved by quantitative fluorescence image analysis using antibodies directed against tumor-associated antigens. The chance of subsequent tumor following initial complete resection is significantly lowered compared to resection alone by either intravesical adjuvant chemotherapy or immunotherapy. BCG is superior to chemotherapy in patients with high risk for recurrence, adjuvant intravesical chemotherapy does not prevent progression to > T1 when compared with resection alone, BCG may delay progression and the need for cystectomy in high-risk patients (T1, Cis or Cis associated with papillary Ta/T1, > 3 recurrences/year, grade 3 tumors). Oral medication with bropirimine (an interferon inducer) induced complete response in patients with carcinoma in situ, oral Lactobacillus casei prolonged the recurrence-free interval to 1.8 times that in the control group. New compounds for adjuvant treatment of superficial bladder tumors are best first tested on their ablative effects (marker lesion, Cis) prior to be used for prophylaxis.