The renewal for season four comes ahead of the start of season three this fall.

The Diplomat (US) centers on Kate Wyler (Keri Russell), the new American ambassador to the United Kingdom. She’s supposed to be going to Afghanistan. She’s great in a crisis zone. In a historic house… not so much. War is brewing on one continent and boiling over on another. Kate will have to manage international crises, forge strategic alliances in London, and adjust to her new place in the spotlight—all while trying to survive in her marriage to fellow diplomat and political star Hal Wyler (Rufus Sewell).
In season three, Ambassador Kate Wyler lives out the nightmare of getting what she wants. She’s just accused Vice President Grace Penn (Allison Janney) of plotting to kill a terrorist and admitted she’s gunning for the vice presidency. But now that the president is dead, Kate’s husband Hal may have accidentally killed him, and Grace Penn is the leader of the free world. None of this slows down Hal’s campaign to get Kate the vice presidency. Kate steps into a role she never wanted, with a freedom she never expected, an increasingly complicated friendship with Secretary of State Austin Dennison (David Gyasi), and a nerve-wracking relationship with First Gentleman Todd Penn (Bradley Whitford).
Ali Ahn, Rory Kinnear and Ato Essandoh also star.
The Diplomat (US) has been nominated for multiple awards, including the Golden Globe, Emmy, SAG, PGA, WGA and Critics' Choice Awards. The streamer claims that the series' first season "became Netflix's most-watched title in its first two weeks alone, reaching the Top 10 in 87 countries and generating 173.46 million hours of viewing in the four weeks following its premiere." Additionally, season two of The Diplomat "spent four weeks in the global Top 10 and reached the Top 10 in 70 countries," the company said.