Millennium Challenge Act of 2003 - States that it is U.S. policy to reduce global poverty through increased economic growth by supporting a new compact for global development in which increased support is provided by developed countries to those developing countries that are ruling justly, fostering economic freedom, and investing in their citizens.
Authorizes the President to provide assistance aimed at reducing poverty to eligible developing countries that enter into agreements with the United States establishing multi-year partnership plans for achieving shared development objectives (Millennium Challenge Contracts). Defines "eligible country" in terms of poverty, commitment to democracy, economic freedom, and investment in its people (including educational opportunity and access to health care).
Establishes a Millennium Challenge Account for the receipt of funds authorized under this Act.
Establishes in the executive branch the Millennium Challenge Corporation to implement the assistance provided under this Act.