Pursuant to a congressional request, GAO reviewed the Department of Housing and Urban Development’s (HUD) efforts to protect children in public housing from lead-based paint hazards, focusing on whether HUD: (1) has complied with lead-based paint legislation; and (2) ensures that public housing authorities (PHA) comply with regulatory requirements. GAO found that: (1) children with elevated blood levels (EBL) who live in public housing containing lead-based paint hazards are not adequately protected from lead poisoning; (2) PHA often do not comply with federal EBL testing requirements and rely on local testing that does not meet HUD requirements; (3) HUD regulatory requirements for EBL children are too narrowly focused; (4) HUD does not ensure PHA compliance with emergency regulations, adequately protect other children living in hazardous buildings, test other units in an EBL child’s building, or warn neighboring residents of potential hazards; (5) PHA often do not meet abatement or relocation requirements for EBL children to comply with HUD requirements; (6) HUD progress in meeting legislative requirements is limited because it has not determined the extent of lead-based paint in public housing and the costs of abatement, completed a comprehensive plan or required demonstration programs, or enforced other related legislative requirements; and (7) although PHA have made limited progress in meeting lead-based paint testing requirements, most PHA abatement efforts are incomplete.