This is a case series of 123 patients with Hirschsprung's disease who were surgically treated with a one-stage transanal endorectal pullthrough by this author and his team in 5 medical institutions in the Philippines. It describes the surgical procedure done and its surgical outcome. Seventy-six patients were 24 months old and younger, 47 were mostly 3 years old and above. Presumptive diagnosis was based on clinical and radiologic evidence, and confirmatory diagnosis on intra-operative frozen section biopsy and postoperative paraffin section. Meticulous attention was given to preoperative colonic saline washout, and intraoperatively to adequate mesenteric vessel ligation and complete aganglionic colectomy with a generous normoganglionic segment. The mean length of bowel resected was 13.9 cm (8.5cm to 32cm), and average operative time, exclusive of the rectal irrigation and frozen section, was 120 minutes (80 to 210 minutes). Surgical morbidity was noted in 16 percent of patients (4 wound infections, 5 bleeding, 1 twisted anastomosis, 8 concentric rings, and 2 posterior wall edema). Medical morbidity was 7% (2 febrile episodes from protracted amoebiasis, 5 non-specific enterocolitis, 1 gastric bleeding, and 1 gastric distention). Normal bowel movement was achieved within 3 months by 97 patients (79%), within 6 months by 24 patients (19%), and more than a year in 2 patients (2%). There was no incidence of recurrent constipation. Children with soiling responded to toilet training. There was no mortality.