Idiopathic pulmonary fibrosis, 1 of the 7 idiopathic interstitial pneumonias, carries an ominous prognosis. It has a median survival of 2.8 years. However, there is significant heterogeneity in the actual length of survival, which varies from months to >5 years. Unfortunately, in addition to lung transplantation, no known medical intervention alters the natural history of the disease. Currently, many phase-III clinical trials are ongoing, but there is no Federal Drug Administration approved therapy. Thus, it is important for the clinician to be able to evaluate prognostic factors. These will help him draw conclusions about the possible course of his idiopathic pulmonary fibrosis patients and make important therapeutic decisions (lung transplantation).