This chapter serves as a primer on the EU’s political and legislative system, exploring the lines of conflict in the context of judicial politics most pertinent to the reform of public procurement regulation. All institutions partaking in the making of EU law bring distinctive incentives and constraints to that process. Its complexity and potential for cross-issue linkages have meant that the formal legislative procedure has been supplemented with informal elements, most notably the trilogue between Council, Parliament and Commission. Against this background, the CJEU plays a deeply entrenched part in the context of EU decision-making in terms of polity-construction, shaping EU law and fostering compliance with it. The chapter explores why, although certain factors may limit CJEU discretion, their cumulative impact is not unequivocal.