Following continent bladder substitution there are several diversion specific complications the urologist has to be aware. The most common complications requiring immediate attention are pyelonephritis, metabolic disturbances and urinary retention. The cause of urinary tract infection and ascending pyelonephritis is most often reservoir outlet obstruction with increased residual urine. Metabolic disturbances are a frequent early complication after bladder substitution with an intestinal segment. Especially salt-losing hypovolemic state and hyperkalemic, hypochloremic acidosis may occur. Therefore, venous blood gas analysis helps with diagnosis and drainage of the bladder as well as peroral Sodium Bicarbonate serves as immediate therapy. The reasons of urinary retention besides recurrent cancer are outlet obstruction because of infection due to increased mucous production, urethral strictures, ileo-urethral stenosis, recurrent prostatic adenoma and protrusion of reservoir mucosa into the outlet. Fortunately, most cases of mechanical outlet obstruction can be treated endoscopically. The risk that these problems occur can be lowered by meticulous follow up of the patients allowing recognition and treatment of increased post void residuals and urinary tract infection as well as providing an adequate sodium bicarbonate substitution.