Contents : 1. The importance of the avian immune system and its unique features 2. Structure of the avian lymphoid system 3. Development of the avian immune system 4. B cells, the bursa of Fabricius and the generation of antibody repertoires 5. Avian T cells: antigen recognition and lineage 6. Structure and evolution of avian immunoglobulins 7. Avian innate immune responses 8. The avian MHC 9. Avian antigen presenting cells 10. Avian cytokines and chemokines 11. Immunogenetics and mapping immunological functions 12. The avian mucosal immune system 13. The avian enteric immune system in health and disease 14. The avian respiratory immune system 15. The avian reproductive immune system 16. Avian immunosuppressive diseases and immune evasion 17. Factors modulating the avian immune system 18. Autoimmune diseases of poultry 19. Tumours of the avian immune system 20. Practical aspects of poultry vaccination 21. Comparative immunology of agricultural birds 22. Ecoimmunology Appendix A. Genetic stocks for immunological research Appendix B. Resources available for studying avian immunology