How we approach duration of anticoagulation in patients with a first VTE event. VTE recurrence risk is primarily informed by an initial evaluation of risk factors. We discuss an initial plan with the patient at the time of VTE diagnosis regarding the likely duration of anticoagulation, based on an evaluation of the circumstances in which the VTE occurred and bleeding risk. After a limited period of anticoagulation (typically 3 months), we schedule a consultation⁴⁴  to confirm whether extended anticoagulation is warranted based on initial risk factors, ongoing risk factors, bleeding risk, gender-specific considerations, comorbidities, potential additional personalized risk factors, and patient preferences, particularly in situations where the optimal duration of anticoagulation is less clear. This discussion guides our evidence-based shared decision making on duration of anticoagulation. Patients whose initial event occurred in the context of a major, transient/reversible provoking factor (such as major surgery or surgery with general anesthesia for >30 minutes) are recommended by international guidelines to receive limited-duration anticoagulation (red light).^2,43  In contrast, those with an unprovoked VTE event and other VTE events associated with a high predicted recurrence risk (and who have a low bleeding risk) are recommended by guidelines to receive extended or indefinite-duration anticoagulation (green light). Emerging data may in the future guide optimal management of patients with higher or lower personalized risk (orange light): for simplicity, in this figure the strength of recommendation, where indicated, is in accordance with the ESC 2019 Guideline on Acute PE.²  *Class I B (ESC ‘is recommended’; data derived from a single randomized clinical trial or large nonrandomized studies). **Class IIa level A (ESC ‘should be considered’; data derived from multiple randomized clinical trials or meta-analyses). ^#Class IIa level C (ESC should be considered; consensus of opinion of experts and/or small studies, retrospective studies, registries), although the relative strengths of recommendations are in line with other similar guidelines. AC, anticoagulation. ^$At least 1 previous episode of VTE not related to a major transient or reversible risk factor. Low HERDOO2 risk: ≤1 HERDOO2 criteria (hyperpigmentation, edema, or redness in either leg; D-dimer level ≥ 250 μg/L; obesity with body mass index ≥ 30 kg/m²; or older age ≥ 65 years).¹⁸