Children with ataxia-telangiectasia (A-T) and cancer have a poorer prognosis due in part to increased treatment-related toxicity. We piloted a curative intent approach in five children with A-T who presented with advanced stage (III, n = 2; IV, n = 3) B-NHL (diffuse large B-cell lymphoma, n = 4; Burkitt leukemia, n = 1) using a modified LMB-based protocol. Two achieved sustained CCR (one, CCR at 6 years; one, pulmonary death after 3 years in CCR). Two died from toxicity during induction and 1 failed induction with progressive disease. Novel therapeutic approaches which overcome drug resistance and are less toxic are needed for children with A-T and B-NHL.