Derbyshire sign former West Indies seam bowler Ravi Rampaul from Surrey on a three-year contract.
Derbyshire all-rounder Luis Reece signs a new three-year deal with the club until the end of the 2020 season.
The 23-year-old was arrested in July in connection with two alleged incidents in Derbyshire in June.
South African Daryn Smit signs a one-year contract extension with Derbyshire to prolong his deal until 2019.
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