Objectives To investigate the technique of laparoscopic pyeloplasty in children with pelvi-ureteric junction (PUJ) obstruction. Patients and methods Six children, aged between 2.5 and 15 years, were treated by laparoscopic pyeloplasty in a prospective study, The outcome was assessed by post-operative isotopic renography. Four of the children underwent a Y/V plasty of the PUJ structure and one a Hynes-Anderson dismembered pyeloplasty, Results One case (the first in this series) was converted to open pyeloplasty due to adhesions around the PUJ from previous surgery, One patient developed an abdominal haematoma at the trocar site, which resolved without treatment. All anastomoses were completed without complication. Five of the children had normal or significantly improved drainage times on post-operative renography, In one patient. the drainage time deteriorated post-operatively, although differential function of the operated kidney improved. Conclusions These early results suggest that laparoscopic pyeloplasty in children is feasible, safe and effective; a longer term follow-up is awaited.