The interstitial lung diseases are a heterogeneous mix of fibrotic and inflammatory lung conditions that cause variable lung function decline which limits lifespan. Patients with these disorders are often difficult to manage given their overlapping and nonspecific clinical phenotypes, unpredictable disease course, and relative paucity of effective therapies. In theory, molecular biomarkers could be broadly applied to improve the care of ILD patients through objectively defining diagnostic subtypes, refining prognosis and disease course expectations, and even tailoring personalized treatment plans. The genetic underpinnings of ILD have been greatly expanded in recent years with several seminal discoveries that could be leveraged into genetic biomarker applications. Although these discoveries have significantly improved the understanding of ILD pathobiology, translating markers of genetic variation into reliable biomarkers requires rigorous evaluation and analytic validation prior to being incorporated into routine clinical practice. In this chapter, we will review the required characteristics of genetic biomarkers, outline the known genetic architecture of ILD with respect to potential genetic biomarkers, and highlight how ILD genetic features could be utilized in clinical practice.