There should be an arbitration agreement between concerned parties in order to resolve a dispute through arbitration. The arbitration procedures, including the selection of the arbitrator and the adjudicative rights of the arbitrator, are based on the arbitration agreement. In other words, the arbitration procedure and adjudication can be carried out within the boundaries of the arbitration agreement. Traditionally, the Doctrine of Separability of the arbitration agreement has been acknowledged in order to emphasize its importance and to clearly separate it from the contract. Today, when the Doctrine of Separability of the arbitration agreement is well established, overemphasizing this separability could hamper its effectiveness and the autonomy of the parties. Moreover, arbitration agreements in the past were required to be written, clarifying the existence of the agreement and determining the scope of its validity. Further, an arbitration agreement was considered as narrowly as possible. However, since arbitration has become a generalized resolution for disputes, the formal or content requirements should be reconsidered. In terms of validity, the subjective and objective scope should necessarily be extended as a means to resolve disputes related to an arbitration agreement and reduce the resolution cost and duration. Under this perspective, the arbitration theory should now focus on arbitration agreements rather than the place of arbitration. We should break from the nationalistic view, which understands that the arbitration system is a part of the national legal system and that arbitration is allowed solely by permission of the nation. Instead, we should extensively reinterpret the subject of arbitration agreement and its range of effects so that disputes can be resolved between the concerned parties under a single procedure and norm, a necessary step forward. Moreover, in spite of the positive contribution and role of the New York Convention toward the establishment and development of the international arbitration system, there should be an effort to overcome its deterioration. As mentioned in the recommendations regarding the interpretation of the arbitration agreement in the New York Convention in 2006, we should begin by striving to match the Convention as a means of interpretation with the changes of the twenty-first century. Ultimately, we should meet the demands of the new era through amendments to the Convention.