The overall objective of the Polish guidelines for the prevention and treatment of venous thromboembolism is to increase patient benefit and safety by appropriate prevention and treatment of deep vein thrombosis and pulmonary embolism as well as proper management of the complications associated with antithrombotic and thrombolytic therapy. These guidelines apply to adult trauma, cancer, surgical, and medical patients as well as those at increased risk of venous thromboembolism. Specific recommendations have been formulated for pregnant women, patients requiring surgery while receiving long-term oral anticoagulant treatment, and patients undergoing regional anesthesia and/or analgesia. We systematically identified all current clinical practice guidelines concerning the prevention and/or treatment of venous thromboembolism and assessed their methodological quality using the AGREE instrument. We chose to update existing Polish guidelines by adapting the most recent high quality guidelines that we identified to Polish cultural and organizational setting rather than develop all recommendations de novo. We based our recommendations primarily on the 8th edition of the American College of Chest Physicians (ACCP) Evidence-Based Clinical Practice Guidelines on Antithrombotic and Thrombolytic Therapy and on the European Society of Cardiology (ESC) Guidelines on the Diagnosis and Management of Acute Pulmonary Embolism. To make recommendations regarding specific management issues that had not been addressed in ACCP guidelines, or whenever panel members felt they needed additional information to reach the decision we also consulted guidelines developed by other professional societies and organizations as well as additional sources of evidence. For each recommendation we explicitly assessed its relevance and applicability in the context of health care system in Poland. We adapted recommendations when necessary, explicitly stating the rationale for modification and judgements about the values and preferences we assumed. We developed original recommendations on the use of new oral anticoagulants that have recently become available, following the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.