Nanotechnological approaches promise considerable potential for the treatment of pneumological diseases, especially asthma and COPD (Chronic Obstructive Pulmonary Disease). At present numerous nanotechnological approaches are under examination, which allow a controlled release of encapsulated drugs or diagnostics. These include nanocarriers composed of polymers or anorganic materials, liposomes, micelles, quantum dots, dendrimeres, polymer conjugates and other systems. Polymeric nanocarriers give the opportunity to control the temporal as well as the spatial distribution of drugs within the lung. By varying the composition, structure and dimension nanoparticles could offer a controlled and prolonged duration of effect of the encapsulated drugs as well as a regional and cell-specific drug targeting within the lung.