On September 17, 1787, the Founding Fathers signed the U.S. Constitution. For the past 225 years, the Constitution has served as the supreme law of the land. The Constitution, along with the Bill of Rights and other amendments, define our government and guarantee our rights. Each year, on September 17, Americans celebrate Constitution Day and Citizenship Day. In addition, September 17-23 is also recognized as Constitution Week. During this time, USCIS encourages Americans to reflect on the rights and responsibilities of citizenship and what it means to be a U.S. citizen.