The EU is founded on certain values such as respect for human rights, democracy and the rule of law. The respect and protection of these values, both internally and in its external actions, constitute its hallmark. However, in recent years, these values have been threatened from within and from outside. The serious and repeated violations of the principles of the rule of law in some Member States such as Poland, Hungary and, more recently, Slovakia, as well as the difficult situation in the international landscape, pose significant challenges that the EU must face with firmness and determination. Is it prepared to do so? Does it have adequate mechanisms to deal with violations of its founding values? This chapter analyses the different tools available to the EU for this purpose.