The sixth generation Ford Mustang (S550) is the current iteration of the Mustang pony car manufactured by Ford. In departure from prior Mustang models, the sixth generation Mustang includes fully independent rear suspension on all models, as well as an optional 2.3L EcoBoost turbocharged and direct injected four cylinder engine. The new Mustang was introduced as a 2015 model year vehicle, marking the fiftieth anniversary of the Ford Mustang, which was revealed as a 1965 model year vehicle on April 17, 1964. The sixth generation is also the first Ford Mustang to be marketed and sold globally, and represented the first time that factory right hand drive Mustangs were produced in addition to the left hand drive models. This is part of the "One Ford" business plan, which also applies to the Fiesta, Focus, Fusion/Mondeo, Escape, Kuga, Edge, Ford Transit Connect, and Ford Transit, as well as other models.

Development of the 2015 Mustang, codenamed "S550", began in 2009 under chief engineer Dave Pericak and (from late-2009) exterior design director Joel Piaskowski, shortly after the updated 2010 model year Mustang went on sale. In December 2010, an exterior design theme proposal by Kemal Curic from Ford's Cologne, Germany design studios was selected by design management. Curic (also responsible for the 2011 Focus (2012 in the US) and the 2014 Mondeo/Fusion) relocated to Ford's design studios in Dearborn in January 2011. During mid-stage development, Curic's original exterior design proposal was eventually rejected by Ford executives, resulting in rapid design changes. After reviewing 3 different exterior theme proposals (A, B, and C) in design clinics in September 2012, the final exterior design (Theme A) was approved by Ford management, with the final design freeze occurring in December 2012, 20 months ahead of originally scheduled August 2014 production. The interior design program began in the spring of 2010, under Doyle Letson. By late 2011, a final interior proposal was settled on and was combination of Theme A & B. In June 2012, the final interior design was frozen. The first test mules in 2010 model year bodies were spotted earlier in June 2012, and the first S550 prototypes were built five months later (exterior design freeze) in May 2013. Mustang