The aim of this introductory paper is twofold.First, we seek to illustrate which are the difficulties intowhich one runs when one attempts to give a precise definitionof what bioart is. Our hypothesis is that every attemptat such definition runs into a paradox. Indeed, if onthe one hand, every definition seems inevitably reductionist,unjustly omitting one or more elements, on the otherhand, defining and constraining the study area is a necessarypreliminary step to understand the artistic phenomenonknown as bioart. In the second part of our paper, attentionwill be focused on the ethical issues that bioartconfront us with. These issues are all the more relevant,given the fact that bioartists often make use of biotechnologiesto manipulate living organisms for artistic purposes