This Chapter gives a brief overview on the EU procurement rules relating to CPBs and joint purchases. The Chapter takes a closer look at how the rules regarding CPBs have development and the main issues relating to the rules in the Directive. The Chapter’s main focus is laid upon what constitutes a CPB and what are the main roles of a CPB. Another topic addressed relates to cross-border procurement. A provision regarding liability between CPBs and their user was inserted in the 2014 Directive with the main aim to reduce the risk for users. The Chapter examines these rules, which also shows that there are still some grey areas. Finally the topic of CPBs and competition law is addressed and its discussed whether CPBs should be covered by competition law.