Facing the threat of climate change and loss of biodiversity, sustainability has become an essential public issue. Zoos as environmental organisations and leaders in conservation have a sustainable responsibility and could contribute to stem climate change and the exploitation of resources by reducing their environmental impact. With the help of the WAZA Conservation and Sustainability Strategy the WAZA sought to stimulate member zoos to work towards sustainability by reducing their environmental footprint or demonstrating methods for visitors to adopt sustainable lifestyles. The presumed barriers for zoos to integrate sustainability to a greater extent are the lack of financial and human resources as well as the lack of information. Therefore, this research was conducted to gain insight into the status quo of integrated sustainability components in five WAZA member zoos and to reveal reasonable and beneficial sustainability technologies and management implementations in terms of small- and large-scale projects considering financial and operational expenses, profitability as well as environmental impact.