Objectives: To describe the outcomes of balloon catheter dilation of the lacrimal duct as the first surgical treatment for older children (≥18 months) with nasolacrimal duct (NLD) obstruction and to examine the effect of the type of obstruction on outcome. Design: Retrospective noncomparative case series. Participants: Seventy-six children 18 months or older with NLD obstruction who had not undergone previous surgery. Intervention: The patients underwent NLD probing, infracturing of the inferior turbinate, and balloon catheter dilation of the distal NLD. The type of obstruction was noted at surgery. Main Outcome Measures: Outcomes were considered excellent if the patient had complete resolution of epiphora and dacryocystitis and normal tear drainage on examination, good if the patient had only minimal residual symptoms or a minimally delayed dye disappearance test result, fair it the patient had moderate residual symptoms or delayed tear drainage, and poor if there was no improvement. Results: Seventy-six children were treated. Overall, results were excellent in 28 (37%) patients, good in 30 (39%), fair in 13 (17%), and poor in 5 (7%). Forty-eight (63%) of the patients had simple membranous obstruction at the Hasner valve. Results were good or excellent in 35 (73%) of these patients. Twenty-eight (37%) patients had stenosis that extended along the length of the distal NLD. Results were good or excellent in 23 (82%) of these patients. Conclusions: Balloon catheter dilation is probably more effective than simple probing for older children with NLD obstruction because of stenosis that extends along the distal NLD. The procedure does not provide a significant advantage over simple NLD probing in patients with typical membranous obstruction at the Hasner valve.