The development of laparoscopic pyeloplasty has progressively led to a reduction in the amount of perioperative renal pelvic excision as a large excision leads to a longer anastomosis with associated increased risks (leak, operative time). This prospective study of 40 patients (29 male, 11 female, aged three months to 15 years) with anteroposterio (AP) diameters of >40mm, were randomised into two groups (A – pelvic reduction, B – non reduction) after open pyeloplasty. After a mean follow-up of nine months (6-12 months) the authors found that there was no difference in renal function, drainage or complications. Two patients from group A and three from group B needed redo pyeloplasties. The authors conclude that pelvic reduction is not necessary in a dismembered pyeloplasty.