A 3-year old boy who had acquired HIV infection transplacentally and developed AIDS encephalopathy is reported from the Depts of Paediatrics and Immunology, Newcastle General Hospital, Newcastle upon Tyne, England. During hemophilus influenza pneumonia at 26 months his speech regressed to expressive aphasia and he developed spastic diplegia with inability to walk. CT scan showed cerebral atrophy. CSF showed no cells and normal glucose and protein; IgG antibodies to HIV were increased. Treatment with intravenous gammaglobulin 300 mg/kg and oral zidovudine (Retrovir-Wellcome) 100 mg/m 4x daily every 4 weeks for 8 months led to considerable clinical improvement and an almost normal CT. Spasticity regressed allowing him to run unaided and his speech in single words became articulate. [1]