[4] James-Turner has previously played for English FA Women's Super League clubs Arsenal, Bristol Academy, Notts County, Yeovil Town, Everton, Reading, and Tottenham Hotspur, as well as American clubs North Carolina Courage and Orlando Pride in the National Women's Soccer League.

[9] She made her senior first team debut on 5 October 2011 as a 63rd-minute substitute for Gilly Flaherty in a 6–0 home win over Belarusian side Bobruichanka Bobruisk in the UEFA Champions League round of 32.

[14] James-Turner played in 13 of Bristol's 14 league games during the 2013 FA WSL season as the team earned their highest ever finish, runners-up behind Liverpool.

"[17] Having stated her desire to remain in the top-flight, James-Turner signed for Notts County in March 2016 ahead of the 2016 FA WSL season.

Two days prior to the start of the FA WSL Spring Series in April 2017, Notts County folded, leaving the players without a club.

[23] James-Turner captained Reading on 7 October 2020 in their 4–0 win over second division Charlton Athletic in the League Cup group stage in the absence of Natasha Harding.

[25] On 24 February 2021, Reading announced that James-Turner had agreed to join North Carolina Courage of the American National Women's Soccer League (NWSL) upon the completion of the 2020–21 FA WSL season in May.

In her final season with the team, James-Turner led the FA WSL in successful tackles with 46 and was one of three outfield players to play all 1,980 minutes along with West Ham's Grace Fisk and Manchester United's Millie Turner.

[27] Having agreed terms in February, James-Turner joined North Carolina Courage in May after the end of the 2020–21 FA WSL season.

[32] On 30 July 2022, it was announced that James-Turner had signed for English WSL side Tottenham Hotspur on a two-year deal with the option of a further year.

Despite the team losing all three group games and failing to score, James-Turner's performances earned her a place in 22-player the Squad of the Tournament, Wales' sole representative.

[2] On 27 October 2011, James-Turner made her senior international debut, aged 17, as a late substitute in a 2–2 draw with Scotland at Tynecastle Park during UEFA Women's Euro 2013 qualifying.