The royal couple arrived at a Mind event at Harrow College in North London on Saturday (10 October) to meet young people who have suffered from mental health issues.
The Duke and Duchess of Cambridge spoke to young people who now volunteer for the charity after having dealt with their own mental health problems.
William and Kate also participated in a Mindkit workshop, which aims to educate young people about emotional health and resilience.
As usual, Kate looked sophisticated in a black and white patterned 'Paulina' dress by US designer Tory Burch, which she wore last year in New Zealand.
It's not the first time the couple have attempted to highlight mental health issues via their important roles.
The Duke recently took part in an anti-bullying workshop run by the Diana Award charity.
Meanwhile, the Duchess visited the Anna Freud Centre, a leading organisation working in the field of children and young people with mental health issues.
Mind says: "Work to build awareness and understanding of mental health problems is a major priority for both The Duke and Duchess.
"They are committed to raising awareness about the mental health problems faced by young people and we are grateful that they have chosen to champion Mind's work.
"We hope it will inspire a new generation of young people to not be afraid or ashamed to talk about mental health problems."
Last month, Kate made a secret visit to a women's prison.
She visited HMP Send, near Woking, where she met inmates battling alcohol and drugs addiction.
It marked her official return to Royal duties from maternity leave, after welcoming daughter Princess Charlotte in May.
This is her second child with husband William - Prince George turned two in July.
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