The Google driverless car is a project by Google that involves developing technology for autonomous cars. The software powering Google's cars is called Google Chauffeur. Lettering on the side of each car identifies it as a "self-driving car." The project is currently being led by Google engineerSebastian Thrun, director of the Stanford Artificial Intelligence Laboratory and co-inventor of Google Street View. Thrun's team at Stanford created the robotic vehicle Stanley which won the 2005 DARPA Grand Challenge and its US$2 million prize from the United States Department of Defense.The team developing the system consisted of 15 engineers working for Google, including Chris Urmson, Mike Montemerlo, and Anthony Levandowski who had worked on the DARPA Grand and Urban Challenges.

The U.S. state of Nevada passed a law on June 29, 2011 permitting the operation of autonomous cars in Nevada. Google had been lobbying for robotic car laws. The Nevada law went into effect on March 1, 2012, and the Nevada Department of Motor Vehicles issued the first license for an autonomous car in May 2012. The license was issued to a Toyota Prius modified with Google's experimental driverless technology. As of April 2012, Florida became the second state to allow the testing of autonomous cars on public roads. California became the third state to legalize the use of self-driven cars for testing purposes as of September 2012 when Governor Jerry Brown signed the bill into law at Google HQ in Mountain View.