Book excerpt: Interstitial lung disease (ILD) is a broad category of lung diseases that includes more than 150 disorders characterized by scarring or fibrosis of the lungs. In Pulmonary Arterial Hypertension and Interstitial Lung Disease: A Clinical Guide, renowned experts provide a state-of-the-art overview of the problems seen by physicians in the clinical management of ILDs. Divided into two sections, the first part provides and update on general issues and introduces both interstitial lung disease and associated pulmonary hypertension. A detailed analysis of the pathology of the various interstitial lung diseases is also provided. The second part addresses specific categories of disease. Bronchiolitis, hypersensitivity pneumonitis, and other conditions are covered, and the use of inspiratory and expiratory high resolution CT scan is discussed as well. This important new text is an invaluable resource for the practicing physician who must be aware of the broad and troubling manifestations of interstitial lung disease.