This chapter turns from captivity after wars, to captivity during wars. It argues that in the 1768 and 1787 Wars, the Ottoman state created a “prisoner of war” system by taking captured enemy combatants—soldiers and sailors—into its own custody, rather than allowing soldiers to sell them. They were no longer valued primarily for labor, ransom, or sale. Indeed, at times the Porte even saw them as a burden. The Ottoman state may have undertaken this initiative in order to make the Law of Release easier to implement: if it held those captives about whom Russian diplomats were the most concerned—captured combatants—in its own hands, diplomatic tensions might be lowered. This chapter traces, in turn, the creation of the prisoner-of-war system, its basic structure, its limitation to the Ottoman state’s corridors of power, and European observers’ recognition of it.