Pulmonary fibrosis is a progressive lung disease characterized by scarring and stiffening of lung tissue, ultimately leading to respiratory failure. Prior lung inflammation from viral infections (e.g., COVID-19) and interstitial lung diseases can be major contributors. Understanding the mechanisms behind its development is crucial, as currently no effective treatments exist to halt or reverse this condition. To address this knowledge gap, researchers have employed various in vitro models, including 2D cell cultures, 3D cell cultures, and ex vivo lung models like PCLS. Precision-cut lung slices (PCLS) offer a unique advantage by preserving the lung's native 3D structure and containing all lung cell types. This makes them ideal for investigating lung diseases and assessing novel therapy safety, toxicity, and efficacy. Generating human PCLS (hPCLS) requires meticulous technique. This presentation will explore how to successfully prepare precise and reproducible hPCLS from surgical lung resections. We will cover proven strategies for inducing fibrosis within this model using a specific mixture of factors known to induce fibrosis. Additionally, we will discuss methodologies for precise hPCLS characterization and the assessment of antifibrotic drug candidates. Importantly, hPCLS maintain viability for at least 14 days, making them ideal for investigating the effects of repeated dosing. In conclusion, this presentation will focus on the valuable application of human precision-cut lung slices for investigating respiratory diseases like pulmonary fibrosis. Their unique ability to maintain viability and mimic the lung's natural structure makes hPCLS ideal for studying disease mechanisms, evaluating potential therapies, and assessing the effects of repeated dosing.