What is the title of the fourth film in the Mission: Impossible series?

The fourth film in the Mission: Impossible series is Mission: Impossible – Ghost Protocol.

Released in 2011, Ghost Protocol follows Mission: Impossible, Mission: Impossible 2, and Mission: Impossible III. The subtitle refers to a protocol activated after the IMF is blamed for a devastating international incident. Ethan Hunt and his remaining teammates must operate without official support.

Brad Bird directed the film, with Tom Cruise returning as Ethan. Jeremy Renner joined the series as William Brandt, while Simon Pegg’s Benji Dunn became a more prominent field operative. Paula Patton played Jane Carter.

The subtitle is often mixed up with Rogue Nation, the fifth film, or Fallout, the sixth. Dead Reckoning Part One is a later entry and uses a two-part subtitle. Counting only released feature films, Ghost Protocol is clearly the fourth installment.