In the traditional administrative law paradigm, Congress chooses which agencies it wants to act and delegates policy-making authority to those agencies. The president can supervise the agencies but he cannot select different agencies to act. This Article offers a revision of this conventional understanding of agency selection. It shows that presidents continually select which agencies act by exercising a set of statutory and constitutional powers that the Article refers to as the president’s agency selection powers. The Article describes how the president’s agency selection powers diversify the president’s tool kit for controlling administrative decisions. The Article also rejuvenates a largely forgotten, century-old debate on the desirability of presidential instead of congressional agency selection.