Hundreds of streakers have run through London Zoo to raise money for the Sumatran Tiger Campaign.
As a group of tigers is called a streak, the zoo came up with the idea to have 300 people streak through the enclosure.
The runners were completely naked apart from a pair of trainers and a few painted as tigers.
Only 300 of the tiger subspecies remain in the wild.
Streak For Tigers raised £40,000 which will be used it to fund conservation work of the critically endangered animals.