Kratos Defense & Security Solutions, Inc. is an American technology company with manufacturing concentrations in weapons and military electronics. It is headquartered in San Diego, California, United States. Customers include the U.S. federal government, foreign governments, commercial enterprises and state and local government agencies. The company is divided into 6 divisions.

Some of Kratos' most recent products are part of a Pentagon effort to invest in businesses in Silicon Valley.

Kratos Defense & Security Solutions was founded as Wireless Facilities Incorporated (WFI), a company whose primary market was the building and support of the telecommunications infrastructure and networks. In 2004, the company primarily sold its services to the US Government, mostly the U.S. Department of Defense.

From 2004 to 2009, the company acquired several companies in the federal services business. Acquisitions included several small public safety firms and mid-sized professional services firms such as:

In September 2007, the company's name was changed to Kratos Defense & Security Solutions.

On July 27, 2011, Integral Systems merged with Kratos. Integral Systems provided services regarding the handling of data from space and terrestrial-based platforms into networks for military, government, and commercial satellite and aerospace customers.

Integral Systems employed about 800 people in 14 locations, and had 6 subsidiaries:

In February 2019, Kratos purchased Florida Turbine Technologies.