The Compact Clause is a provision in the United States Constitution found in Article I, Section 10. It prohibits states from entering into agreements or compacts with each other without the consent of Congress. This clause ensures that states do not form alliances that could undermine federal authority or disrupt national unity. The purpose of the Compact Clause is to maintain a balance of power between the states and the federal government. By requiring congressional approval for interstate agreements, it helps prevent conflicts and promotes cooperation among states while safeguarding the interests of the nation as a whole.