Firms that ignore mental health issues risk "breaking employees' lives and families", the boss of Lloyds Banking Group has warned.
Companies not paying attention to mental health also incur huge costs to the economy, research suggests.
Employees' mental health issues cost businesses over £40bn a year, a study by consultancy Deloitte found.
It found one factor was staff spending unproductive hours at work when ill, rather than taking time off.
Lloyds boss Antonio Horta-Osorio is someone with personal experience of how workplace stress can affect anyone - including the top brass.
The year was 2011. Banks were still reeling from the ravages of the great financial crisis with another one threatening the eurozone imminently.
Britain's biggest retail bank. Lloyds, was in poor financial health. Antonio Horta-Osorio knew it - and it started to affect his own health.
"I was very mindful that the bank was in a very weak position to face adversity. It was a problem that was going around my mind constantly, which led me to sleep less and less. And the less and less sleep progressively led me to exhaustion, and then to not sleeping at all which was a form of torture so I had to address it and I did".
With the consent and understanding of the board, he took eight weeks off to recuperate before returning himself, and ultimately the bank, to health.
That personal experience led him to re-evaluate the importance of mental health for all of the bank's 65,000 employees.
Senior executives, including Horta-Osorio, underwent a mental health awareness programme while thousands of mental health first aiders were trained throughout the bank with an online portal being set up for staff. They were encouraged to use it if they were struggling with issues either at work or in their private lives.
They also increased their employees' insurance cover for mental health to the same level as that of physical health.
"I had the advantage in the sense of having had a personal experience that helped me be being more sensitive, but I don't think that is a must. You don't have to have been through that. I learned the hard way. At least one out of three people goes through a mental health problem through their lifetime. So it is actually much more common than you might think."
While I was in his offices overlooking St Paul's Cathedral, he showed me an email that had just arrived in his inbox from an employee who expressed gratitude for Horta-Osorio's acceptance of personal difficulty that had helped to de-stigmatise issues around mental health in an industry not known for its honesty in talking about personal problems.
Is it easier or more difficult to take time out if you are a wealthy and successful chief executive?
It is certainly pretty rare and Horta-Osorio is reluctant to take a view.
"I think when you have a very visible and public position, it's probably more difficult to leave the bank for a few weeks. But I don't want to prejudge because I think every case is different and people will have their own views."
Far from the world of high finance, poor mental health exacts a heavier price in other businesses. Construction is an industry that has always understood the importance of physical health and safety but mental health has been a silent killer. Suicide is almost four times more common in construction than in other industries.
On a housing development in Salford, Nicola Hodkinson, business services director, of construction firm Seddon said the suicide of one of their employees had changed the way they manage mental health at their sites.
Jordan Bibby joined the company as a 16 year old apprentice and took his own life at the age of 25 in 2017.
The company named a mental health programme after Jordan, and Emma Dempster now trains the companies' mental health first aiders. I asked her what they were looking out for.
"People who become withdrawn - or go the other way and are quick to anger. If they increase their drinking or change their eating habits. If their physical appearance changes - if they are not looking after themselves. All of these are signs they may be struggling".
There is only so much employers can do Nicola Hodkison admits.
"I can't fix people. I'm not a counsellor, I can't be responsible for people's lives, but I am responsible for them while they're at work.
"So we can try and make the culture at Seddon one where people can be open and honest and authentic, and that they can have a conversation to say, 'I'm not OK, can we have a chat about it to let you know what's going on in my life'"
Colleagues, family and friends said that there were no outward signs that Jordan Bibby was in danger of taking his own life. It's arguable whether any of their new workplace policies would have changed what happened.
In fact other surveys show that nearly half of employees still feel uncomfortable discussing personal mental health issues with their employer.
It is 31 years to the week that I - and my three younger brothers - lost our own father to suicide caused by stress, anxiety and depression.
I have been struck - moved even - by the efforts of some businesses to play their part in tackling a problem that costs the economy billions and more importantly can shatter lives and families.
Antonio's top tip? Look after your sleep.