Earth will plunge into darkness later this month for World Wide Fund for Nature's (WWF) Earth Hour.
The Earth Hour is an annual event, on Saturday (March 28), in which people turn off all their lights and electronic items as a symbolic gesture for their love of planet earth.
It happens every year for one hour, between 8.30 and 9.30pm, starting in Samoa and ending in Tahiti. Last year, a record 162 countries took part.
Earth Hour was a massive success last year, with even the Houses of Parliament and Big Ben switching off their lights, so make sure you get involved.
Whether you'll be partaking in candlelit yoga, eating with your family or reading a book in the glow of the moonlight, get your lights off and help save the planet!
Sign up to the earth hour by visiting the WWF Earth Hour website.