A series of 161 bladder cancer biopsy specimens (survival data available in 122 cases) was analysed immunohistochemically for the expression of E-cadherin (E-CD), the most important cell-to-cell adhesion molecule in epithelial cells. Altogether, 81% of the tumours were E-CD-positive, the staining being heterogeneous in nearly all tumours. Normal transitional epithelium was positive for E-CD while in carcinomas the expression was reduced or even absent (18%). Lower levels of E-CD were detected in rapidly proliferating high-grade muscle-invasive tumours. Reduced expression of E-CD was related to a dense inflammatory cell reaction in tumour stroma. The median clinical follow-up was 12.0 years. Short recurrence-free survival of Ta-T1 tumours (P = 0.02) was related to expression of E-CD fewer than 50% of cancer cells. In survival analysis the fraction of E-CD-positive cells (P = 0.1) and the expression intensity of E-CD (P = 0.09) showed a non-significant association to prognosis. Multivariate survival analysis indicated that expression of E-CD has no independent prognostic value over grade or stage while recurrence-free survival was related to E-CD expression.