Sussex sign South Africa all-rounder Vernon Philander as an overseas player for the first half of the 2017 season.
Clink McKay is named Leicestershire limited-overs captain for 2017, with Mark Cosgrove continuing as four-day skipper.
Former England international Mal Loye joins Derbyshire as their new development coach.
Derbyshire sign South Africa fast bowler Hardus Viljoen as a non-overseas Kolpak player on a three-year contract.
Audio & Video
Former England rugby union international Rob Andrew discusses taking over as Sussex chief executive and his love of cricket.
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How to get into Cricket
How to get into cricket - physical exertion with a chess-like element in matches which range from half an hour to five days.