Based on the results of large clinical trials, several low-molecular-weight heparins (LMWHs) have been approved for prophylaxis and the treatment of venous and arterial thromboembolism. As a result of expiration or pending expiration of patent protection of the originator LMWHs, many generic or biosimilar LMWHs have been approved in some countries and more are likely to be approved elsewhere. Their greater availability may reduce the treatment costs. The Working Party on Requirements for Development of Biosimilar LMWHs of the Subcommittee on Control of Anticoagulation, Scientific and Standardization Committee of the International Society on Thrombosis and Haemostasis has reached a consensus on recommendations to ensure the quality of biosimilar LMWHs as compared with the originator LMWHs.