|The chapter aims at presenting a practically orientated survey of major problems of a clinical picture and therapeutic pitfalls in pulmonary embolism (PE) affected patients from the point of view of a geriatrician. Growing number of PE people of advanced age and considerably small awareness of this fact in wider medical public makes this chapter highly significant. Pulmonary embolism (PE) in the elderly represents immediate threat of life. Especially in old age clinical signs of PE are non-specific and could be both underdiagnosed and overdiagnosed. The high occurrence of PE (particularly its silent form) is of crucial importance in the elderly mortality. Our recommendations would like to emphasize the need of no underestimation of this fact and to carry out preventive measures in all age groups (including “oldest old” and frail persons. Thrombembolism is the most common cause of death, and a major cause of morbidity, in later life. Like cardiac and arterial thrombembolism, the incidence of venous thrombembolism increases exponentially with age. Since the inpatient mortality in general hospitals is about 10%, it is estimated that about 1% of patients admitted to the hospital die of PE. However, for every patient who dies of PE in a surgical ward, three die in nonsurgical wards. In the great majority of patients dying of PE, previous venous thrombembolism was not diagnosed or treated. DVT (deep venous thrombosis) is often nonocclusive and hence clinically silent prior to embolization; while nonfatal PE occurring prior to the fatal one may not be recognized clinically, especially in older patients who frequently have cardiorespiratory symptoms, such as a heart failure or chronic obstructive airways disease. Prophylaxis against PE is of paramount importance because venous thromboembolism is difficult to detect and poses an excessive medical and economic burden. Mechanical and pharmacologic measures often succeed in preventing this complication. The hypothesis that the combination of immobility and coagulation activation predisposes to DVT formation is supported by the prophylactic efficacy of both mechanical measures which increase leg vein blood flow, and antithrombotic drugs especially anticoagulants. We would like to emphasize the need of permanent thinking of the possibility of PE in elderly persons with present risk factors and also the requirement of correctly assessed diagnoses and the start of therapeutic procedures as soon as possible.