Electric propulsionElectric propulsion isElectric aircraft considered the third revolution in aviation, following heavier-than-air flight and the jet engine. However, before it can become as ubiquitous as jet propulsion, it needs to reach a stage of maturity where it can be readily certified by the relevant governmental authorities. This will ensure that it is a technology that is safe and reliable to operate for and around the public. In this chapter, we will outline some of the challenges that electric propulsionElectric propulsion might face in the certification process. We will also discuss recent changes in the rules, mainly in the United States (FAAFederal Aviation Administration (FAA)) and in Europe (EASAEuropean Union Aviation Safety Agency (EASA)) with respect to certifying such aircraftAircraft and we will outline the role of standards development organizations such as SAE International and ASTM. The certificationCertification landscape is tough, and it will be hard for applicants to obtain the necessary approvals, but it is equally clear that authorities and industry stakeholders are eager to make sure that there is support for their endeavors so that this new revolution in aviation an actually succeed.