. . "Cytological investigation of the pulmonary tract is one of the most useful diagnostic tests available to the clinician. A wide range of samples can be provided to the laboratory from a variety of sampling techniques. In many cases, the cytologist can provide a clear diagnosis of malignancy, infection, or other specific disease. Even if a diagnosis cannot be offered, the sample frequently aids the clinician with future management by providing reassurance that tumor is unlikely to be present (in the appropriate clinical and radiological setting). This chapter outlines the various samples that the cytopathologist may be faced with and provides a description of the microscopic features that aid diagnosis." .