The legitimacy of the EU has been constantly questioned. In this context, one can come across the problem of the democratic deficit that the Union arguably suffers from. At least partially, the objective of EU citizenship was to tackle the democratic deficit. This chapter looks into how Union citizenship responds to this problem. It begins by looking into the notion of the democratic deficit, pointing out its divergent understanding and contestability. Then, the chapter proceeds to consider the specific means EU citizenship employs to react to the democratic deficit, namely through the European Parliament, the right to petition the Parliament, the European Citizens’ Initiative, and the European Ombudsman.