In this article, we provide the rationale for the ELOPE (Evaluation of Long-term Outcomes after Pulmonary Embolism) Study, a prospective, observational, multicenter cohort study of patients with a newly diagnosed, first episode of pulmonary embolism (www.clinicaltrials.govNCT01174628) that aims to identify clinical, anatomic, physiologic and biomarker determinants of poor outcome after pulmonary embolism.Pulmonary embolism, the most serious form of venous thromboembolism (VTE), leads to the hospitalization or death of over 30,000 Canadians, 225,000 Americans and 300,000 Europeans each year, numbers that have risen over the past decade. Although numerous studies have evaluated optimal approaches to the diagnosis and treatment of pulmonary embolism, their focus has primarily been on short-term outcomes such as mortality and recurrent VTE in the days, weeks or months after pulmonary embolism diagnosis. However, it is increasingly recognized that pulmonary embolism may have long-lasting sequelae that impact on patients' health. The objective of this article was to review the available evidence on long-term clinical, functional, anatomic and physiologic outcomes after pulmonary embolism, and discuss avenues for research in this field, including the ELOPE Study. Residual pulmonary vascular abnormalities on follow-up imaging and echocardiogram are frequent in pulmonary embolism patients, but the clinical significance of these abnormalities is poorly understood. Whether initial and/or residual clot burden, recurrent pulmonary embolism, altered pulmonary artery or right ventricular hemodynamics or other prognostic factors such as biomarker levels contribute to long-term morbidity after pulmonary embolism is as yet unknown. The ELOPE Study will describe and identify the predictors of long-term outcomes after pulmonary embolism in the setting of a rigorous, multicenter cohort study in which long-term clinical, anatomic, physiologic and functional sequelae such as quality of life, return to work and loss of productivity after pulmonary embolism are systematically evaluated.