This book highlights recent advances in the understanding of interstitial lung disease (ILD) from diagnosis to treatment. The first part of the book discusses general aspects of ILD, such as genetics, epidemiology, classification, pathophysiology, pathology, imaging, and clinical approach including management of ILD comorbidities such as gastroesophageal reflux and pulmonary hypertension. The second part describes common ILDs like idiopathic interstitial pneumonias, sarcoidosis, and hypersensitivity pneumonitis as well as ILDs associated with connective tissue diseases or induced by exposure to environmental agents, drugs, and radiation. Lastly, the third part of the book is devoted to rare ILDs including eosinophilic lung disease and reports on current therapy guidelines.