Homeland security is officially defined by the National Strategy for Homeland Security as "a concerted national effort to prevent terrorist attacks within the United States, reduce America's vulnerability to terrorism, and minimize the damage and recover from attacks that do occur".

Market research organizations estimate that the addressable U.S. market over the next five years will be in the range of approximately $140 billion, a 21% increase over a five-year estimate made in 2004. It is expected that this market will continue to grow at a steady combined annual growth rate of between 8% and 10% over the next five years. This assessment is based on a number of factors, including in-depth analysis of policy priorities, government spending trends, corporate demand, technology innovation and adoption cycles. These realities have been driven by some important factors over the past two years that have had an effect on the near-term direction of the market.

• The persistence of a legitimate terrorist threat to the U.S. and many other nations.Despite the absence of a major attack in the U.S., the continued threat posed by al Qaida, related groups and other terrorist organizations, along with several successful attacks overseas and the public reporting of the disruption of major plots, has led to continued focus on the need for enhanced security products.
• The evolution of DHS Department of Home Land Security and its effect on the market and policy