訴之合併，不論是人的合併或請求的合併，傳統上縱有訴訟經濟和矛盾裁判之防止作為訴訟法上正當化的理論根據，惟此兩種型態之合併，除了帶給原告和法院極大的方便，對原告的程序利益極度傾斜之外，對被告的程序防禦權可謂有害無益。其中對於訴之客觀合併，國際社會上的立法例對此作為國際裁判管轄權之基礎，雖非將之列為絕對禁止的管轄原因，但亦非各國普遍接受的最大公約數，對其妥當性外國學說多有爭議。依照我國目前學說與涉外裁判實務以類推適用說為多數見解的情況之下，不僅毫無問題意識，在保護本國民等不能載明在裁判理由的真正動機下容易被視為理所當然。本文旨在就我國完全欠相關基礎研究的情況之下，試圖對此國際裁判管轄各論的理論建構進行檢討。

Where two or more claims are to be made by a single action, such action like joint suit and joinder of claims may be filed with the court which shall have jurisdiction over one of those claims pursuant to the jurisdictional provisions in Taiwanese code of civil procedure. The purpose of these provisions is to avoid a serious risk of inconsistent judgments which might result if the plaintiff had to sue the defendants separately in different forum. These rules permit a plaintiff to sue multiple defendants in the same national court even if some of the co-defendants are not habitually resident in that state, if we also applied these rules to international civil and commercial litigations. However, these rules provide a great convenience and advantage to both the plaintiff and the court, but impose a great burden to foreign defendants.In order to avoid manipulation of jurisdictional requirements by the plaintiff, such as bringing suit against an unrelated defendant in order to gain jurisdiction in a favorable forum, certain conditions must be imposed. After compare the conditions imposed in Japanese law and in the case-law of the European Court of Justice on Brussels Convention/Regulation I Article 6(1), this article examines some recent Taiwanese judgments in related. This article argues that the closed connection between claims should be imposed not only to the joint suit against multiple defendants but also to the joinder claims in international litigations in civil and commercial matters.