This chapter reconsiders some of the zones of contact between the early modern Roman and Spanish Inquisitions. To do so, it focuses on evidence of communication between the two institutions during the later sixteenth and earlier seventeenth centuries. The prevailing scholarly vision of the Spanish Inquisition – and of the governance of the Church throughout the early modern Spanish monarchy – highlights its relative independence from Rome thanks to a host of delegated powers. This chapter seeks to complicate this view by demonstrating the existence of exceptional cases of appeal to Rome from Spanish trials, collaboration in extraditing prisoners, vying over inquisitorial jurisdiction, and attempts to influence the policies and procedures of Iberian tribunals. While Spanish-ruled Sicily and Sardinia were the primary arenas of contestation between authorities, it extended to the inquisition tribunals of the Iberian Peninsula as well. While always the exception rather than the rule, conflicted inquisitorial cases of this kind were also important laboratories for the generation of legal theory and the building of judicial and institutional authority; they were, moreover, one more potential front in complex skirmishes among ecclesiastical authorities, between inquisitors and monarchs, kings and popes.