More than 20,000 people - identified as the next generation of leaders - have attended its courses, but if you are not one of them, you have probably never heard of it.
It is called Common Purpose and prominent supporters include BBC business editor Robert Peston, Assistant Deputy Commissioner Cressida Dick of the Metropolitan Police and numerous top public sector officials.
It’s a not-for-profit organisation which organises training and networking events for high-fliers.
Its website says “Common Purpose gives leaders the inspiration, the knowledge and the connections they need to produce real change - in their workplaces and in their communities.”
According to one Common Purpose “graduate” who spoke to the BBC, Common Purpose’s activities seem innocent enough: delegates attend a week-long residential course, where the emphasis is on personal development and making new contacts.
She said delegates were encouraged to identify their strengths and weaknesses and were taken on outings to a mental hospital, a prison, a local tenants’ association and the City.
But former naval officer Brian Gerrish, who leads a campaign against Common Purpose, says: “It’s a secret society for careerists. The key point is that the networking is done out of sight of the general public.