Several diagnostic and prognostic scores of pulmonary embolism have been developed during the last years. Clinical probability assessment remains the cornerstone of every diagnostic algorithm, and using scores facilitates the process. Clinical probability allows identifying those patients in whom pulmonary embolism can be ruled out in combination with a D-dimer test. It also allows defining which patients should receive anticoagulant treatment while awaiting the results of the diagnostic tests. Prognostic scores have also been developed in order to stratify patients for the different therapeutic options: outpatient or inpatient treatment, anticoagulant treatment or thrombolysis or surgical or endovascular mechanical treatment.