The diagnostics of pulmonary neoplasms has considerably changed in recent years. Based on large-scale molecular characterization studies and the development of targeted therapies, precise morphological, immunohistochemical and molecular pathological tumor subtyping is now of utmost importance for evidence-based treatment decisions. This review highlights recent developments in morphological and immunohistochemical subtyping of pulmonary neoplasms, concepts of tumor progression and provides a preview of relevant changes of the forthcoming new WHO classification, which is expected to be published in 2015. It becomes apparent that a 3-step diagnostic procedure based on morphology, immunohistochemistry and molecular pathology is important to meet the requirements of an increasingly more complex, interdisciplinary care of lung cancer patients and to allow reliable, clinically meaningful tumor diagnosis.