A memorial service is to be held to celebrate the life of former union leader Rodney Bickerstaffe.
Speakers paying tribute on Thursday will include Labour leader Jeremy Corbyn, former deputy prime minister John Prescott and actress Maxine Peake.
Music at the service in Westminster Central Hall, London, will be provided by the Dodworth Colliery Band and the choir of Unison, the union he led from 1996 to 2001.
Mr Bickerstaffe, who died last October aged 72, was general secretary of the public sector union NUPE before it became Unison and was a former president of the TUC.
He also served as president of the National Pensioners Convention (NPC) for four years from 2001.
Unison general secretary Dave Prentis said: "Rodney was a cherished friend and colleague. He was instantly recognisable, utterly unforgettable and loved by many around the world.
"His work continues to change the lives of millions of people including those who never even knew him.
"Rodney had an unswayable sense of social justice as well as a great sense of humour and love of laughter.
"His was a life of campaigning and making a difference, with the minimum wage and the creation of Unison among his many achievements.
"Rodney was the very best of us, a true giant of our movement and we all miss him greatly.
"Part of his legacy is that his life will continue to inspire us all to do more to create a better, fairer world."