Clinicopathologic findings in three cases of inflammatory myofibroblastomas (so-called inflammatory pseudotumors) of the trachea and bronchi are reported. In all cases the myofibroblastic nature of the spindle cell proliferation was revealed using electron microscopic and immunohistochemical methods. In two of these cases, in which the lesions were incompletely excised to conserve the wall of the airways and the normal lungs, several recurrences over a period of many years were successfully managed endoscopically. These potentially recurring and locally invasive myofibroblastic lesions should be treated as low-grade neoplasms rather than reactive processes. However, if complete excision is not feasible, lung-sparing management is warranted because myofibroblastomas progress slowly and recurrences can be readily detected by bron choscopy. Int J Surg Pathol 2(2):93-98, 1994.