There has been a growing and increasingly polarized ethical debate about the role and management of modern zoos. Partly, this debate concerns very idea of having captive wild animals on display, and partly it relates to specific management issues. Whereas zoo supporters tend to agree that zoos have a positive role, how they should be managed is strongly debated within the zoo world. The aim of this presentation is both to clarify the moral principles and values that may underlie the debate, and to suggest ways in which the zoo world can create a fruitful moral dialogue both with the surrounding societies and among its own supporters. We will begin by presenting the in principle discussion about whether or not it is morally acceptable to keep wild animals on display in zoos; and we will state our reasons for finding zoos acceptable in principle. However, this still allows for an important in practiceethical discussion which we will address by focusing on the following four issues: 1) the effectiveness of zoos in achieving conservation goals; 2) how zoos acquire their animals; 3) zoos‘ ability to ensure good welfare for the animals in their care; and 4) how zoos deal with reproduction and ―surplus‖ animals. We will argue that even though all accredited zoos seem to share ethical principles both of conservation and animal welfare, there is room for discussion both about how to interpret the two principles and how to balance or prioritize them in case of conflict. Two cases, one concerning the import of wild African elephants into the US, and the other concerning the killing and subsequent public dissection of the giraffe Marius in the Copenhagen Zoo will serve to illustrate this. We will end up supporting an ongoing and open ethical debate about how zoos should develop.