The proceedings of the IV International Symposium on Breeding Birds in Captivity held in in Toronto, Ontario, Canada from September 7-12th, 2007. The conference theme was Conservation Through Aviculture and had over 50 presenters covering various aspects of aviculture, zoology, avian conservation, medicine and management. With nearly 500 colour pages featuring multiple charts, graphs, figures and tables depicting various aspects of avian husbandry, management and both in-situ and ex-situ conservation aspects. With over 100 international contributors, these proceedings represent possibly the largest compilation of information pertaining to avian conservation breeding to date.