Interstitial lung diseases (ILDs) are a heterogeneous group of disorders characterized by inflammation and fibrosis of the pulmonary parenchyma. Over the past decade, substantial advances have reshaped understanding of these conditions, particularly in disease classification, molecular profiling, biomarker development, imaging modalities, and therapeutic innovation. This chapter discusses the significance of the usual interstitial pneumonia (UIP) pattern as a distinct and prognostically unfavorable subtype. It examines the role of molecular endotyping in refining classification, predicting outcomes, and identifying novel therapeutic targets. The potential utility of emerging biomarkers for diagnosis, prognostication, and assessment of treatment response is reviewed. Imaging advances, including quantitative computed tomography (QCT), functional respiratory imaging (FRI), and xenon magnetic resonance imaging (Xe-MRI), are analyzed in the context of disease diagnosis, monitoring, prognosis, and pathophysiology. Finally, recent progress in therapeutic strategies is summarized, with attention to agents such as inhaled treprostinil, nerandomilast, and other promising investigational compounds. Collectively, these developments underscore a rapidly evolving landscape that is transforming the clinical management of ILDs.
