The city academy programme was originally based on the programme of City Technology Colleges (CTCs) created by the Conservative government under Margaret Thatcher in the 1980s, which were also business-sponsored.
Currently, the Government is encouraging CTCs to convert to academies; several have already done so (for example, Djanogly CTC is now Djanogly City Academy).
Academies differ from CTCs in several ways; most notably, academies cannot select more than 10% of pupils by ability[citation needed], whereas CTCs can.
Academies have been compared to US charter schools, which are publicly funded schools largely independent of state and federal control.