Middlesex won their first Championship title since 1993 on the final day of the 2016 season
With the 2017 season here, stay up to date with the latest player signings, moves and speculation from all the counties.
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
REL: Released
RET: Retired
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 2016 season are included on the 2016 list. Have we missed anyone? Please let us know.
Overseas player: Jeevan Mendis (Sri Lanka, until June); Imran Tahir (South Africa, from June after Champions Trophy); Matt Henry (New Zealand, for Twenty20)
Other news: The county have announced a new coaching set-up, with ex-captain Kim Barnett as director of cricket, supported by Twenty20 specialist coach John Wright, first XI support coach Steve Stubbings and development coach Mal Loye. AJ Harris has left his post as academy director, while seamer Tony Palladino has taken a player-coach role. Durston's departure leaves a vacancy as limited-overs captain.
DURHAM
Overseas player: Stephen Cook (South Africa, for first half of season); Tom Latham (New Zealand, for second half of season)
Overseas player: Neil Wagner (New Zealand, for first half of season); Mohammad Amir (Pakistan, from 19 June); Tamim Iqbal (Bangladesh, for Twenty20 match on 9 July)
Possible signings: Hampshire are reportedly interested in Worcestershire all-rounder Moeen Ali, who will be out of contract at the end of the summer, though Warwickshire are favourites for his signature and Middlesex are also rumoured to be interested.
Other news: Hampshire were reprieved from relegation because of Durham's financial problems. Craig White has replaced Dale Benkenstein as head coach. Overseas signing Bailey will skipper the County Championship side once he arrives in May, with club captain James Vince still leading in limited-overs cricket.
KENT
Overseas player: Wayne Parnell (South Africa, until mid-May); Adam Milne (New Zealand, after Champions Trophy); Yasir Shah (Pakistan, 8 June-6 July); Jimmy Neesham (New Zealand, for Twenty20)
Possible departures: England spinner James Tredwell has asked to speak to other counties because of a lack of playing time, while batsman Daniel Bell-Drummond has been linked with Warwickshire. Both are out of contract at the end of the season.
Possible signings: Middlesex are reportedly interested in Worcestershire all-rounder Moeen Ali, who will be out of contract at the end of the summer, though Warwickshire are favourites for his signature and Hampshire are also rumoured to be interested.
Other news: Ex-New Zealand captain Daniel Vettori has joined as Twenty20 head coach, with McCullum replacing Dawid Malan as T20 captain.
Other news: Ex-England batsman James Taylor has joined as a coaching consultant, with former Northants captain David Sales taking a part-time coaching role.
Overseas player: Kumar Sangakkara (Sri Lanka); Aaron Finch (Australia, primarily for Twenty20 but also as Championship cover while Sangakkara is at the Caribbean Premier League); Moises Henriques (Australia, for Twenty20 while Sangakkara is at the CPL)
Overseas player: Vernon Philander (South Africa, until mid-June); Ross Taylor (New Zealand, for Twenty20); Jerome Taylor (West Indies, for One-Day Cup group stage)
Possible signings: Ex-Leicestershire batsman Angus Robson has joined on what the county describes as "a season-long trial" in which he will be registered to play for the 2nd XI and in the Sussex Premier League, as he looks to earn a full contract.
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 reportedly interested. Warwickshire have also been linked with a move for Kent batsman Daniel Bell-Drummond.
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.
