The Duke of Cambridge has called on chief executives and businesses to help end the stigma surrounding mental health in the workplace.
William told an audience of business leaders in London: "As a pilot working with an air ambulance charity, I have seen first-hand how work can affect individuals' mental health. "Mental health exists, just as physical health exists. It is no big deal."
The Duke called on businesses to sign the "Time for Change Employer Pledge", which commits them to change the way mental health is spoken about in the workplace. Mind, the charity behind the pledge, said about £26 billion is lost every year in the UK due to workers taking time off with mental illness.
William continued: "All of the air ambulance team know that we can get help for what is going on in our heads if we need it. "We know where to turn as practical help is well signposted, and we know that no-one will judge us if we do admit to difficulties. Fortunately, the rewards of such an open approach are worth it for the employer, too."
The event was hosted by Unilever, whose chief executive Paul Polman said he was inspired to make mental health a priority in his workplace after seeing employees and fellow executives suffer, and following the suicide of a good friend. "You all have daughters, you all have sons," he appealed to the business chiefs. "It is an issue that affects us all."
William also spoke to charities who help companies understand mental health in the workplace.
He told Calm, the Campaign Against Living Miserably, that people "go through the physical processes... but no-one examines the mental".
The Duke said in his speech: "Catherine, Harry and I have been campaigning on this issue for only a few months now, but what we have observed already is that when we get our heads together, when we talk and listen to family, to friends and colleagues, we share the load. "It is really that simple: a problem shared is a problem halved."
David Titman, marketing manager at Unilever, suffered from depression and bereavement, which led to him needing time off work. He praised the support Unilever gave him, which included getting him counselling, and encouraged people to seek help. The 31-year-old said: "Find someone. If you have to go to your boss's boss, or even higher, find someone that you feel you can confide in. "Having the conversation with anyone is step one."
Statistics from Mind show mental health is now the leading cause of sickness absence in the UK, but 95% of employees calling in sick with stress give a different reason for their time off work.
William said: "For too long, held back by stigma, shame and fear, people have found it difficult to open up to others about those times when their mental health needs support. "Without employers committed to changing attitudes, we would be pushing a rock uphill - but, with you, we can and will change the way we think about mental health in this nation."