Gareth Batty steps down as captain of Surrey, and is replaced by Rory Burns for first-class and One-Day Cup matches.
County champions Essex begin the defence of their title in 2018 against Yorkshire at Headingley on 13 April.
Australia batsman Aaron Finch signs a two-year contract to play Twenty20 cricket for Surrey.
England quartet Mark Stoneman, Ben Foakes, Jason Roy and Tom Curran extend their Surrey deals for at least three more years.
Audio & Video
Former Sri Lanka captain Kumar Sangakkara reflects on his career as he plays his final first-class match for Surrey.
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