Continuing advances in imaging technology have resulted in an improved ability to evaluate thoracic malignancies with PET. Published reports demonstrate that PET provides accurate, noninvasive detection of malignancy that is useful in the characterization of nonspecific radiographic lung lesions, staging of known lung cancer, and identification of recurrent disease. Preliminary studies suggest that PET may also be able to accurately assess therapeutic response. The incorporation of PET into routine clinical practice has advanced rapidly and undoubtedly PET will continue to be an increasingly important part of the clinical assessment of patients with lung malignancy.