The duchess said racism and unconscious bias 'lies and thrives' in 'quiet moments'.
Racial justice, gender equity, mental health and the environment are some of the subjects they are set to cover.
It's been argued that Meghan's speech would have been too political to be made if she was a senior royal.
Meghan has previously spoken about what it meant to grow up as a mixed race woman in America.
Prince William has been quietly volunteering for the 24/7 crisis text line Shout, which he launched with Kate Middleton, Prince Harry and Meghan Markle.
The royals have been spotted multiple times in this summer wardrobe staple.
Her dress designer said the duchess to be was "serene and utterly stunning" as she prepared to marry Prince Harry.
The Duke and Duchess of Sussex have reportedly agreed to pay £18,000 a month in rent on their Windsor home.