International trade in fauna and flora is curently considered as one of the greatest threats to populations of many wildlife species. According to available information, some species are declining mainly due to persecution by people for meat or for trade. Illegal trade is increasing as well. Its yearly turnover is estimated to be in the order of billions of US dollars. This diploma theses analyzes the international trade with selected bird species under the CITES Convention - Asian hornbills, African turacos, South American tukans and arassari, and pigeons and doves during the period from 1990 till 2015. Although the CITES Convention has proven to contribute to protecting biodiversity and protecting endangered species by monitoring and regulating the trade with them, it has its limitations and shortcomings. These are described in this diploma thesis on the example of some specific cases.