As beginnings go, it was not promising. The intern was late for his first meeting with his mentor at the Chicago law firm. And yet things worked out OK. More than three decades later, the mentee, Barack Obama, and his mentor and later wife, Michelle, are still together after eight years in the White House.

That the Obamas’ relationship started in the workplace is hardly unique. A survey this year from the Society for Human Resource Management found that 27 per cent of US workers have had an office romance.

Financial Times