This chapter focuses upon the European Parliament (EP), an institution that has seen its power dramatically increase in recent times. The EP has been transformed from being a relatively powerless institution into one that is able to have a genuine say in the legislative process and hold the European Union’s executive bodies (the Commission and Council, introduced in Chapters 9 and 10) to account in a range of policy areas. However, increases in the Parliament’s formal powers have not been matched by an increase in popular legitimacy: turnout in European elections is falling. Thus, while the EP’s legislative power is comparable to that enjoyed by many national parliaments, it has struggled to connect with the wider European public. The chapter explores these issues in detail. In the first section, the EP’s evolution from talking shop to co-legislator is reviewed; its powers and influence are explained in the next section; the EP’s internal structure and organization are then discussed with a focus upon the role and behaviour of the political groups, and finally, the European Parliament’s representative function as the EU’s only directly elected institution is discussed.