The Women's Super League transfer window opens at the end of June but players are already on the move as they look to finalise deals before this summer's Women's World Cup.
Manchester United are competing in Europe for the first time and will hope to bring in more quality, while Manchester City are likely to dip into the market after finishing fourth in the league.
Champions Chelsea have already done some early business, while clubs at the bottom of the WSL are planning squad rebuilds.
Here are a few things that could happen in the transfer window which runs from 26 June to 14 September.
After two failed world-record bids for Manchester United's Alessia Russo in January, Arsenal maintain heavy interest and have held discussions with the England striker over a move when her contract expires this summer.
Manchester United have been in negotiations over a new deal with Russo for several months but risk losing her, with clubs in the National Women's Soccer League (NWSL) and Europe also keen.
United and Spain full-back Ona Batlle could also leave on the expiry of her contract with Barcelona's long-term interest remaining.
An option to extend United goalkeeper Mary Earps' contract for another year has been exercised but they face a battle to keep her with several clubs keen to sign her in this window.
Chelsea are favourites to sign USA forward Catarina Macario after her Lyon contract expired, and have reportedly agreed
a deal to sign Paris St-Germain defender Ashley Lawrence.
Aston Villa are hopeful of signing Manchester United winger Kirsty Hanson and Arsenal defender Anna Patten on permanent deals following successful loan spells. They must agree a sale with United for Hanson and face competition from Brighton for Patten's signature, but Villa are favourites.
Villa are also seeking a new goalkeeper with England international Hannah Hampton turning down a contract extension amid interest from top sides in the WSL, and from two Spanish clubs.
Manchester City forward Jess Park attracted interest following her impressive loan spell at Everton, but is expected to remain at the club to compete for a place next season.
Recently departed Manchester City winger Hayley Raso is set to join Real Madrid after arranging a medical, despite several WSL clubs including Tottenham declaring a late interest in signing her.
Netherlands and Twente goalkeeper Daphne van Domselaar has been a target for a few WSL clubs, while Leicester are hopeful of signing Bayern Munich's Janina Leitzig on a permanent deal despite competition from Manchester United.
Bayern Munich goalkeeper Janina Leitzig was impressive in her short loan spell at Leicester City
Manchester United manager Marc Skinner said they will strengthen in the transfer window in preparation for Champions League football, and have reportedly made an offer
for 19-year-old Netherlands forward Esmee Brugts, who also has interest from Manchester City.
Despite reports suggesting Manchester United were interested in Atletico Madrid midfielder Maitane Lopez Millan, it is understood she is likely to move to the NWSL.
United goalkeeper Emily Ramsey is out of contract and was wanted by Everton in January, where she enjoyed an impressive loan spell this season.
Everton defender Rikke Sevecke will leave when her contract expires and is expected to join an Italian club in Serie A.
Wolfsburg forward Rebecka Blomqvist is a target for several WSL clubs including Everton and Brighton, but is believed to have been offered an attractive deal to stay in Germany.
Manchester City may renew their interest in Everton defender Gabby George, while Brighton defender Poppy Pattinson has had an offer from the NWSL.
West Ham defender Grace Fisk is out of contract this summer and has attracted attention from Real Betis, AC Milan, Chicago Red Stars and several WSL clubs.
The Hammers have some key players out of contract this summer including England defender Lucy Parker, who has sparked wide interest. Meanwhile, defender Melisa Filis is likely to leave the club.
Elsewhere, Liverpool have looked at a few attacking options and are favourites to sign young Sheffield United forward Mia Enderby. They have also shown interest in AC Milan striker Martina Piemonte - along with Everton.
The Reds have also enquired about Australia goalkeeper Teagan Micah and Scotland defender Jenna Clark, though they face competition from clubs in Germany.
Relegated Reading will switch to a part-time set-up so could lose several senior players including Wales' Gemma Evans who has attracted interest from at least four WSL clubs.
Tottenham assistant manager Vicky Jepson took over as interim boss and led them to WSL safety
West Ham are looking at candidates to replace Paul Konchesky, who departed as manager at the end of the season, while Manchester City are set to offer a new contract to manager Gareth Taylor.
Tottenham are also in talks with several candidates for their managerial position, including interim boss Vicky Jepson, who helped them survive relegation and is highly regarded at the club.
Away from the WSL, Lyon striker Signe Bruun, who was a late January target for Arsenal, is close to a move to Real Madrid.
Lyon's former Ballon d'Or winner Ada Hegerberg, who has had interest from Barcelona, has just one year remaining on her contract and it is understood talks about a renewal have not yet begun.
Pernille Harder (left) and Magdalena Eriksson (right) joined Bayern Munich after winning the WSL with Chelsea