We reviewed 60 urethral fistulas in 50 patients seen between 1974 and 1979. After the results of this study were assessed technical aspects of the repair were incriminated to account for the 40 per cent failure rate for first-time closure of urethral fistulas in our area. To study this problem an animal model was created in the laboratory. A comparison was made between classically repaired fistulas and those repaired with microsurgical equipment and techniques. In the group repaired by a classical macrosurgical technique only 20 per cent of the repairs were successful, while 90 per cent of the repairs under the microscope succeeded. Techniques and material, as well as histology involved, are presented in detail. Some of the causes of fistula repair breakdown clarified in this study include tissue trauma “para fistula” fistulas due to needle trauma and nonrecognition of multiple small additional fistulas. Details of 25 fistulas in 19 patients in whom closures were done with microsurgical techniques are presented. Success rate for primary closure was 88 per cent.