Casandra "Cassie" Ventura is taking the stand in Sean "Diddy" Combs' criminal trial, almost two years after she sued her ex-boyfriend.

As Sean "Diddy" Combs' trial unfolds in NYC, here's what to know about Cassie Ventura and other the key witnesses in the case.

Follow the latest from Sean "Diddy" Combs' sex trafficking trial in N.Y. as Cassie Ventura testifies against the artist for the second day in a row.