This chapter provides detail description of FNAC in lesions of lung. Chapter has 12 well illustrated diagrams and pictures. Inflammatory lesions of lung, specific infections of lung, granulomatous inflammation of lung, squamous cell carcinoma of lung, bronchogenic adenocarcinoma of lung, carcinoid, pulmonary blastoma, and metastatic malignancies of lung are described in detail with the help of excellent illustrations and histopathological pictures. All salient features of different lesions are highlighted in 13 boxes. 3 tables are included to provide details of difference between bronchial cell and malignant cells, differential diagnosis of small cell carcinoma and special stains to differentiate mesothelioma from adenocarcinoma for easy learning. 15 references are included at the end of the chapter to facilitate further reading.