his article analyzes the issue of the United States president's right not to execute statutes that he in good faith considers to be unconstitutional. Such a right has been claimed by presidents since the times of Thomas Jefferson and Andrew Jackson. After a historical introduction, the article analyzes principal arguments in support of and in opposition to executive non-enforcement of unconstitutional statutes. Among the former, there are arguments derived from the presidential oath of office, from the principle of separation of powers, and from the analogy with judicial review. Among the arguments against presidential nonenforcement are arguments that the Constitution requires the president to take care that all laws be faithfully executed, that presidential non-enforcement is equivalent to an unconstitutional absolute veto, and that it infringes on exclusive rights of the judiciary. These arguments rest on a misunderstanding of the principles of constitutional supremacy and judicial review. The article also demonstrates that the Constitution provides sufficient means to guard against abuse of executive non-enforcement. The article therefore concludes that the president is permitted to disregard unconstitutional statutes. It also analyzes circumstances in which such disregard is appropriate, concluding that the president should be guided by principles of deference and accommodation of the views of other branches.