Judicial and scholarly discussions about checks and balances almost always focus on actions and reactions by domestic actors. At least in the intelligence area, however, foreign actors can have direct and indirect influences on US checks and balances. New national-security challenges require increased cooperation with foreign intelligence partners. Leaks and;voluntary transparency mean that far more information is publicly available about intelligence missions. And robust legal rules now bind the United States and other Western intelligence services. These changes create opportunities for foreign leaders, citizens, corporations, and peer intelligence services to affect the quantum of power within the executive or the allocation of power among the three branches of the US government. First, some of these foreign influences can trigger the traditional operation of checks and balances in the US system. Second, these foreign actions simulate some of the effects produced by US checks and balances, even if they do not stimulate the US system to act endogenously. Whether one views these foreign constraints as positive or detrimental, understanding them is critical to an informed conversation about the extent to which the executive is truly unfettered in the national-security arena.