John Browne, who was the chief executive of the energy company BP between 1995 and 2007, kept his sexuality secret for the first 50 years of his life.

After being outed by the Daily Mail in 2007 he became the first person, leading a major publicly-traded company, to acknowledge that he is gay. But he later stepped down after revelations about his homosexual affair.

In 2014 he published The Glass Closet: Why Coming Out Is Good Business.

Lord Browne told Becky Milligan that in the business world it is tough to find role models, and if gay people come in to the sector and see no one like them at the top, they will go elsewhere.

(Photo: Lord Browne, credit: Getty Images)