It has been a turbulent 12 months since the head of the four Tate galleries took the number one spot on this list. While discontent and protest fitfully surfaced from the activist-left over BP’s corporate sponsorship, in the spring it was Serota’s detractors on the right who made the most noise. The conservative press gleefully stretched for Oscar Wilde clichés when Tate lost not one but two directors in quick succession. Was it carelessness on Serota’s part? Perhaps not, but Penelope Curtis leaving Tate Britain for Calouste Gulbenkian Museum after a much maligned five-year tenure, and Chris Dercon announcing his decision to jump ship from Tate Modern to direct Berlin’s Volksbühne (although he’ll be staying in the post until next summer) was not a good look for Serota. 

The ten-storey extension, which dwarfs Tate Modern’s original building like a super cruiseliner on the Venetian skyline, is proving controversial too. Currently four years behind its original opening date – during which performance spaces in the power station’s old oil tanks, opened to much hype in 2012, have sat idle as construction continues above them – the additional space is still missing £30m of funding, although Serota says he is confident this will be found before the new launch date of June 2016. Last year’s top spot came in recognition of Tate’s vast international network of global acquisitions committees and internationally active curatorial teams. No change there. Nor has all the construction dented its exhibition programme (Tanks aside) and general popularity with punters: a(nother) record – 7.9 million visits across all four sites in 2014–15, with 5.7 million alone stepping into Tate Modern. But with his legacy projects nearing completion, is the sixty-nine-year-old eyeing retirement in some pleasant corner of Southern England?.