British Royal Catherine, Duchess of Cambridge Went To Jail On Friday (25sep15) To Discover What Life Is Like Behind Bars.
Prince William's wife visited inmates at a women's prison in Surrey, England in conjunction with the charity Rehabilitation of Addicted Prisoners Trust (RAPt).
The Duchess was able to see an addiction treatment program in action and learn about how inmates with substance abuse issues can be helped.
During the visit, the royal said, "I was reminded today how addictions lie at the heart of so many social issues and how substance misuse can play such destructive role in vulnerable people's lives. I saw again today that a failure to intervene early in life to tackle mental health problems and other challenges can have profound consequences for people throughout their lives."
The Duchess met many of the inmates and talked to them about their recovery.
The visit comes just days after Catherine ended her maternity leave and returned to work.
She gave birth to the couple's second child, Princess Charlotte, in May (15) and took the rest of the summer off.
The royal went back to work on 17 September (15) with a visit to the Anna Freud Centre in London, which provides care for vulnerable youngsters with mental health problems.