Post-pulmonary embolism (PE) syndrome is a broad term representing a spectrum of diseases that may occur following an acute pulmonary embolism. These disease processes include markers of decreased quality of life such as post-PE dyspnea, with objective evidence of decreased cardiopulmonary function, chronic thromboembolic disease, and chronic thromboembolic pulmonary hypertension. While the terminology of post-pulmonary embolism syndrome may be unfamiliar to some, it has become an increasingly recognized entity. There seems to be a disproportionate number of patients following an acute PE that exhibit signs of post-pulmonary embolism syndrome compared to those that undergo further screening following acute pulmonary embolism. This indicates that perhaps there is a paucity of educational material or screening guidelines among those taking care of patients following an acute pulmonary embolism. This chapter will help define, recognize, and understand the basic screening process for patients following acute PE that are at risk or showing signs of post-pulmonary embolism syndrome.