Excitonic Properties of ZnO

In the first chapters we give some short comments on the history of ZnO research and on growth, doping, transport, and deep centers, topics which will be covered in more detail by other contributions to this symposium "ZnO-rediscovered". Then we concentrate in a first main chapter on the band-structure, excitons, and polaritons in the regime of linear optics. The second main chapter deals with many particle effects and lasing. It is followed by a short conclusion and outlook.