This international survey evaluates anticoagulation strategies in ECMO patients across 17 countries. Findings show unfractionated heparin remains the primary anticoagulant, while bivalirudin use is rising. Despite widespread protocol use, significant variability persists in dosing, monitoring, and transfusion practices. Hematology involvement is often limited to complex cases, highlighting the need for standardized, collaborative approaches to improve ECMO outcomes.