With the 2017 season over, stay up to date with the latest player signings, moves and speculation from all the counties ahead of the 2018 campaign.
Counties are allowed to field two overseas players in Twenty20 games, with up to four registered for that competition, although only two can be registered at any one time, and registrations must be for a minimum of 10 days.
Only one overseas player is permitted in the County Championship and One-Day Cup competitions.
Guide to abbreviations
Also shows, where relevant, players' previous counties
KPK: Kolpak contract
YTH: From youth teams
EUP: European Union passport
UKP: Born overseas, but has UK passport
Kolpak contracts are signed by foreign players, using a European Court ruling to avoid counting against the quota of one overseas player per club.
Players who moved counties or retired during the 2017 season are included on the 2017 list. Have we missed anyone? Please let us know.
Other news: Batsman Jack Burnham is banned for the 2018 season after receiving a one-year ban for recreational drug use. The county need to name a new captain for the One-Day Cup and T20 Blast following Jennings' and Coughlin's moves.
Overseas player: Neil Wagner (New Zealand), Mohammad Amir (Pakistan), Tamim Iqbal (Bangladesh)
Other news: Former wicketkeeper Paul Nixon has replaced Pierre de Bruyn as head coach. McKay's departure also leaves them looking for a limited-overs captain, while BBC Radio Leicester has reported that new signing Carberry will replace Cosgrove as Championship skipper.
Overseas player 2017: Adam Voges (Australia), Brendon McCullum (New Zealand), Tim Southee (New Zealand)
Possible signings: Worcestershire all-rounder Moeen Ali, who will be out of contract at the end of the summer, has been heavily linked with a return to Warwickshire, though Middlesex and Hampshire are also reported to be interested. Warwickshire have also been linked with Kent batsman Daniel Bell-Drummond, and are reportedly one of three counties chasing South Africa's Morne Morkel as a potential Kolpak signing for 2018.
Overseas player 2017: John Hastings (Australia), Mitchell Santner (New Zealand). Nathan Lyon (Australia), Ravichandran Ashwin (India)
Possible signings: Last season's main overseas player John Hastings was originally contracted to return for 2018, but is now restricted to Twenty20 cricket by injury. He wants to return for the T20 Blast but the county are "considering all options".
Possible departures: England all-rounder Moeen Ali, who has two seasons to run on his contract, which runs out at the end of the 2018 season, has been heavily linked with a return to Warwickshire, although Middlesex and Hampshire are also reportedly interested. Batsman Joe Clarke has been linked with Nottinghamshire, who deny a deal has already been agreed.
Overseas player 2017: Peter Handscomb (Australia), Shaun Marsh (Australia), Sarfraz Ahmed (Pakistan), Kraigg Brathwaite (West Indies)