Esports, by definition, is a competition, and as in any competition, somebody wants to be the winner. What can people do to enhance their performance and how far should or can they go in that quest for a competitive edge? Regardless of their relative effectiveness, performance enhancement is a part of competition, and the question is what should be allowed (or not) in a competition, either due to ethical or health concerns. Regarding undesired and illicit performance enhancement procedures, it will always be an arms race for regulators against potential users with regard to updating the policies, enforcement, and detection procedures. In this chapter, we will especially focus on pharmaceuticals and non-invasive brain stimulation, as examples for two particularly interesting and regulatory challenging ways of enhancing performance.