International arbitration, as an essential part of any modern legal system, needs provisional measures to protect the rights and interests of the arbitration parties while they are awaiting the final decision of the tribunal. The existence of a legal framework enabling cross-border enforcement of such measures is of great importance in the EU, which allows free movement of citizens, assets and trade within its single European market. However, the enforcement of such measures within the EU lacks a legal framework. This is due, primarily, to two interrelated reasons. The first is the failure of international conventions to address the issue of the cross-border enforcement of provisional measures and to resolve jurisdictional uncertainties between arbitral tribunals and national courts. The second reason is that the EU's attempts to remedy the shortcomings created by international conventions -via the Judgment Regulation ("The Recast") and decisions of the CJEU- have ultimately subverted the very system it sought to enhance. The aggregate effect of this failure has been overall increased complexity. This thesis will try to answer three questions: 1) Is it possible to find a solution to deal with the uncertain positions of arbitration agreements and proceedings within the EU, and can the suggested solution be utilised to help the regulation and use of provisional measures?; 2) Is it possible to harmonise the different approaches taken by Member States' arbitration rules on the jurisdictions of national courts and arbitral tribunals in respect of granting provisional measures?; 3) Is it possible to achieve a cross-border enforcement mechanism for tribunal-ordered and court-ordered provisional measures (in support of arbitration proceedings) in the EU?In order to answer these questions, the thesis proposes the following: (1) Recognising an exclusive jurisdiction for the seat court to decide on the existence of the arbitration agreement; (2) Providing an exclusive jurisdiction for the arbitral tribunal to rule on the existence of the arbitration agreement after its formation; (3) Recognition of a supervisory role for the seat court in granting provisional measures and (4) Enforcement of tribunal-ordered measures in the form of awards. It is hoped that these suggestions will help determine the jurisdictions of arbitration tribunals and national courts in respect of provisional measures and arbitration agreements. It will also create a viable framework for cross-border enforcement of tribunal-ordered and court-ordered provisional measures. It is hoped that these suggestions will consequently help improve the efficiency of arbitration as a valuable form of alternative dispute resolution.