The 29-year-old has signed a three-year deal with the Edgbaston club after four seasons at Hove
Danny Briggs, the left-arm spinner, has joined Warwickshire on a three-year deal from Sussex.
The 29-year-old, who has played a single one-day international and seven T20s for England, spent four years at Hove.
A former Hampshire academy graduate, Briggs has taken 568 scalps across his career in all formats and is the all-time leading wicket-taker in T20 Blast history.
"I’ve had a great time at Hove over the last four years, but I’m delighted to make this move and join Warwickshire and the Bears," said Briggs.
"I like Paul Farbrace’s exciting vision for the Club, and it aligns with what I would like to achieve in the coming years.
"I’m looking to be part of all format success and I haven’t given up a strong desire to play at the highest levels again.”
Sporting Director Paul Farbrace added: "For several years Danny has been widely recognised as one of the leading spinners in the county game and he is an excellent addition to our squad.
"His record in T20, in particular, is outstanding as the leading wicket-taker in the history of the Blast with 172 wickets.
"However, Danny is vastly experienced across all three formats of the game and he knows what it takes to win trophies, having previously been part of teams that won both white-ball competitions.
"We look forward to welcoming him into the Bears squad when the training programme for the 2021 season gets underway in November."
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