In June 2001, Congress and the president approved the Economic Growth and Reconciliation Act of 2001 (EGTRRA), the largest tax cut in two decades. The multiyear cut, scheduled to phase in gradually over the decade, will reduce taxes (and government revenue) by $1.35 trillion by 2010. EGTRRA then "sunsets" on December 31, 2010, restoring the law to its pre-2001 status. This unusual sunset provision, considered a budget gimmick by many analysts, leaves the long-term outlook uncertain. Few observers, however, expect EGTRRA to disappear entirely. The President and many congressional members have already proposed making the provisions permanent. This brief describes the EGTRRA provisions that benefit low-income and middle-income families and children and estimates the effect of the tax cut over the decade. Families with children benefit more than families without children, and families with high incomes benefit more than those with moderate and low incomes.