Trident Juncture 18, abbreviated TRJE18, was a NATO-led military exercise held in Norway in October and November 2018 with an Article 5 collective defence scenario.

The stated goal of Trident Juncture was to train the NATO Response Force and to test the alliance's defence capability.

[3] During the NATO summit in Wales in 2014, the alliance decided to conduct several high-profile military exercises in the coming years.

[8][9] According to the Norwegian Armed Forces, the exercise tested the country's ability to receive and handle large numbers of troops and amounts of materiel and military equipment.

The command post exercise (CPX) lasted from 14 to 23 November 2018 at NATO's Joint Warfare Centre in Stavanger, Norway.

Between the initial preparations and 7 November, NATO and the Norwegian Armed Services received 412 environmental damage incident reports and 51 complaints.

[12] Of these reports, 30 have been traffic collisions between military and civilian vehicles,[12] with accidents occurring even after the peak of exercise's activities.

[13] The Norwegian Armed Forces stopped publishing figures on the complaints and damage reports on 7 November, despite the recurrence of other incidents and press coverage.

[16] On 8 November 2018, while returning from the exercise, the Norwegian frigate Helge Ingstad collided with the Maltese-flagged tanker Sola TS, and began taking in water, as well as leaking about 10 cubic metres (350 cu ft) of diesel.

[18] Seven sailors were injured in the incident and by late morning she had developed a severe angle of list to starboard side with most of the stern submerged.

[21] Admiral Haakon Bruun-Hanssen was quoted saying he largely believed this was due to the professional behaviour of the soldiers during the exercise, and the positive interactions between the armed forces and civilian population.

In those counties where the exercises were held (Trøndelag, Hedmark, Oppland, and Møre og Romsdal), the percentage of respondents who had a positive opinion of NATO rose from 64 to 74%.