Prince Harry says he started the Heads Together campaign to end the "outdated prejudice" surrounding mental health.
Prince Harry
The 32-year-old - who spearheads the charity with his brother Prince William and his sister-in-law Catherine, Duchess of Cambridge - has spoken out about the importance of "speaking about" mental health, as he believes staying quiet about these issues can make them "quickly escalate".
He said: "If you feel stressed or like a cloud is hanging over you, you cannot know how to fix that feeling unless you start speaking about it.
"William, Catherine and I started this campaign because we saw that fear of judgement, stigma, and outdated prejudice meant that too many people stayed quiet about their mental health challenges.
"And we saw that this fear of even talking about a problem often meant that issues could quickly escalate out of hand.
"How is it that for most, the first time mental health is talked about is when they're already suffering?"
And Prince Harry - who served two tours of duty in Afghanistan - drew on his experiences with the armed forces to urge people not to face their mental health battles alone.
He continued: "Stigma cannot and must not be the reason we shy away from equipping ourselves and our families for the day that a dark cloud may appear.
"I have seen the threat that this fear and stigma poses in my work with veterans and my former Army friends.
"Guys and girls in the armed services often need to think they are invincible.
"I know first-hand from my time as an Apache pilot that you do not want anyone to question your ability to cope with pressure and stress."
"When you are called on to assist with a rescue mission in a dangerous situation, you want everyone to know you won't be fazed by the challenge.
"Questioning can bring about doubt, when you know the training will kick in. We all consider ourselves at the top of our game and strive for perfection."
Prince Harry admits "no-one is invincible", and some people can be desperate for help even if they "struggle to admit" it.
Speaking at an event for runners taking part in the upcoming London Marathon - for which Heads Together has been made the named charity - the royal said: "We all want to be as professional as humanly possible. What I've learned through my work with the Army's Personnel Recovery Unit, is that this need to be seen as tough and invincible can follow you home from the battlefield.
"And when the truth is - no one is invincible and anyone who is repeatedly exposed to stress and trauma will need help with their mental health, this pride can become very dangerous.
"I have met too many people who waited too long to start having that conversation. I have met people who disconnected from their spouses and children rather than admit that they needed to speak to someone.
"I have sat with a man who struggled to admit he needed help even as he could not stop shaking and blinking as he fought post-traumatic stress.
"I have met people who considered taking their own lives rather than admit to anything that might make them look weak in the eyes of others."
Tagged in Prince Harry