This review includes the seven idiopathic interstitial pneumonias defined by The American Thoracic Society and The European Respiratory Society 2002 publication. Idiopathic pulmonary fibrosis is the clinical term for usual interstitial pneumonia. The radiologic pattern includes basal and subpleural ground glass and reticular opacities and honeycomb lung. Nonspecific interstitial pneumonia is characterized with a radiologic pattern of subpleural and basal ground glass and reticular opacities. Cryptogenic organizing pneumonia is manifest radiologically by peribronchial ground glass opacities and subpleural consolidation. Acute interstitial pneumonia is the clinical term for idiopathic diffuse alveolar damage and the exudative phase is characterized radiologically with diffuse ground glass opacification and dependent consolidation with the additional feature of lung architectural distortion in the organizing phase. Respiratory bronchiolitis associated interstitial lung disease manifests as centrilobular ground glass opacities on CT. Desquamative interstitial pneumonia is characterized by ground glass opacities with lower zone predominance on CT. Lymphoid interstitial pneumonia manifests by ground glass opacities and nodular interlobular septal thickening on CT. The diagnosis of an IIP should be rendered ideally only after all clinicoradiologic-pathologic data have been reviewed.