For over 30 years the U.S. Environmental Protection Agency (EPA) and its partners have made great progress toward a cleaner, healthier environment for the American people. Following the terrorist events of September 11, 2001, and thereafter, EPA's mission expanded beyond safeguarding the natural environment - the air, water, and land - from traditional sources of pollution. With the Nation under a continuing threat from those who seek to harm it, EPA also has the important responsibility of protecting the environment from terrorist acts. In September 2002, EPA published a Strategic Plan for Homeland Security (2002 Plan). The 2002 Plan reflected the deliberations of the Agency's senior leadership regarding the scope of activities that would appropriately support enhanced and challenging homeland security responsibilities. The 2004 Homeland Security Strategy (2004 Strategy) furthers the Agency's strategic planning process and updates the earlier plan.