This paper outlines arbitral tribunals' power to order provisional measures under the auspices of I.C.S.I.D. Arbitration; that is, investor-state arbitration. The scope of a tribunal's power is cumbersome to discern, especially when there are possible interferences with state sovereignty. More recently, tribunals have ordered provisional measures to suspend a domestic criminal investigation or proceeding. Is this an infringement on a states sovereign prerogatives or a response to, for example, dilatory tactics by a rogue state? The crux of the issue is this: a state will always be in a position to utilize its prosecutorial powers in order to frustrate the arbitration by putting immense pressure on the investor, its employees, or its witnesses, in other words: “playing games” in local courts. In order to guarantee procedural integrity of the arbitration and, as a corollary, the legitimacy of investor-state arbitration in its entirety, the provisional measure is a practical tool that can be used effectively.