People around the world are shaving their heads and snapping selfies to raise money for cancer research, and to show solidarity with those who have lost their hair to cancer treatment.

The “No Hair Selfie” campaign is a World Cancer Day challenge from The Princess Margaret Cancer Foundation in Toronto.

Some especially brave souls have actually parted with all their locks, including economist Don Tapsoctt, whose head was shaved by CTV News Chief Anchor Lisa LaFlamme on Thursday.

There’s also a “virtual” option, where users are downloading a phone app, snapping photos, getting a “virtual shave” and then sharing the results on social media along with #NoHairSelfie.

As of Thursday evening, more than 33,000 people have participated and more than $840,000 has been raised for the foundation.

Online donations can be made until March 31.