Exercise Trident Juncture will involve 36,000 personnel from more than 30 allied and partner nations and will be the culmination of a year of NATO exercises.
Right now the Royal Air Force, already busy with operations over Iraq and deployments around the world, is supporting NATO in the Baltic Air Policing Mission.
Although it's been ongoing since 2004, recent years have seen the UK's involvement increase in the wake of the Ukraine crisis.
However, it's not just the pilots and the aircraft that are based in the Baltic, it involves a range of personnel with different trades and skills.
Forces TV's Laura Hawkins was given an exclusive look at what is involved.