雙邊投資條約之締約國應遵守其條約義務，正如其應遵守契約義務，只不過條約與契約通常各有不同之爭端解決條款。然而在傘狀條款之下，可將地主國所應遵守之契約義務轉化為條約義務，而使根據條約規定所成立之仲裁庭有權審理因契約所生之爭端。在本件涉及水壩工程興建計畫之爭端案當中，ICSID仲裁庭裁定其有樣審理投資人所提之請求，亦即地主國因拒絕投資人建議根據契約之約定將爭端提付仲裁，故違反地主國與投資人母國所締結之雙邊投資條約。不過仲裁庭認為其無權審理投資人所提之其他請求。本文擬就該案所涉及之相關問題予以評析。

The States Parties to the Bilateral Investment Treaty are bound by their treaty obligations as well as their contract obligations, but the dispute settlement procedures in each case are different. However, under an umbrella clause, the host State commits itself to comply with its contractual obligations, thus transforming those obligations into treaty obligations. Such a clause may bring the contract within the Tribunal's jurisdiction based on a treaty. In a dispute arising Out of a dam construction project, the ICSID Arbitral Tribunal found that it had jurisdiction over the investor's claims that the host State, by refusing to accede to the investor's request to arbitration pursuant to the contract, breached the Bilateral Investment Treaty concluded between host State and investor's home State. But the Tribunal decided that it hade no jurisdiction over the investor's other claims. This article aims at examining the relevant issues arising out of this case.