It is odd that it is titled 'gender separation' when they refer to the protected characteristics and 'sex' throughout.
This non-statutory guidance is provided to support schools in identifying what is expected of mixed schools (maintained, academies and other independent) when it comes to separation by sex following the Court of Appeal’s judgment in HM Chief Inspector of Education, Children’s Services and Skills v the Interim Executive Board of Al-Hijrah School [2017] EWCA Civ 1426 (Ofsted v Al-Hijrah).