Kate and Will chose a mental health summit as their first royal engagement after the Duchess' maternity leave.
The Duke and Duchess of Cambridge are due to attend the first Global Ministerial Mental Health Summit - an initiative to help improve mental health around the world.
Today's inaugural summit aligns with the couple's Heads Together charity and their targeted focus on mental health awareness, and is being co-hosted by the British government and the Organization for Economic Cooperation and Development (OECD), and they watched two presentations on successful mental health programmes in the U.S. and Slovenia.
The former Ms Middleton studied Art History at St Andrew's University in Scotland - so we reckon she knows her stuff too.
Kate will meet the curators who have worked on the project before unveiling a plaque to mark the centre's official opening.
The duke and duchess were greeted by Health Secretary Matt Hancock
It's the royal couple's first joint public duty since Kate gave birth to Prince Louis on 23 April.
Their last stop was to a Friendship Bench, part of a innovation program from Zimbabwe which aims to teach elderly Zimbabwean women the skills they need to act as city lay health workers.
For her appearance, Middleton wore a lavender Emilia Wickstead dress and carried a crocodile Aspinal of London handbag, accessorizing her ensemble with nude pumps, silver earrings and a matching necklace.
The couple, along with Prince Harry, have been credited with helping break down the stigma surrounding mental health by encouraging open conversations about it.
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