One in four of us will experience some kind of mental health problem over the course of a year – so most of us will either have experienced it ourselves or know at least one person affected by it.
#1in4 is about breaking through the stigma associated with mental illness and making it easier to talk about your mental health.
The campaign is supported by an incredible group of actors, singers and comedians including Tom Hardy, David Tennant, Olivia Colman, Brian Cox, Sarah Silverman, Russell Brand, Luisa Omielan and Kristen Bell.
From 18th April, these celebrities will launch the campaign by posting selfies in which they’re holding up 4 fingers to highlight the 1 in 4, and you'll also see these selfies posted and shared on BBC Three, Radio 1, BBC News and other BBC sites.
If you’re worried about how you’re feeling there are lots of people who can help. Talk to your family, or a friend, your GP, or call a helpline as soon as you can. Talk to someone before you reach crisis point.
Post your own #1in4 selfie to show your support.