Sir Kevin Barron has announced that he will finish as Rother Valley's MP at the end of the next Parliamentary term.
Sir Kevin's decision brings to an end a Parliamentary career that has lasted more than 30 years, having begun when he was first elected as an MP back in 1983.
Sir Kevin said: "It has been the honour of my life to represent the people of Rother Valley in Parliament for more than 36 years and I sincerely thank all of my constituents for their support over the years.
"But I have made the decision that this Parliamentary term will be my last.
"I am very proud of the work that I have been able to do in Rother Valley and Parliament, in particular leading the way on many of the smoking controls that we now take for granted.
"However, the work I am most proud of is the casework that never makes the headlines but makes a huge difference to people’s lives."
Sir Kevin replaced Peter Hardy as Rother Valley’s MP in 1983 when Mr Hardy switched to a different seat.
Before becoming an MP, he was an electrician at Maltby Colliery for more than 20 years and was president of the Rotherham Trades Union Congress in 1982, as well as being a member of the National Union of Mineworkers.
When he became an MP, he was made Parliamentary private secretary to then Labour leader Neil Kinnock from 1985 to 1988.
He went on to hold Opposition front bench roles under subsequent leaders John Smith and Tony Blair, speaking on employment and health respectively.
He was knighted in 2014 for political and public services.
He continued: "I believe one of the main roles of being an MP is giving a voice to the voiceless and championing campaigns that otherwise would have no chance of success.
"I have always tried to do this throughout my political career.
"None of this work would have been possible without the staff in my office and I would not have been able to do my job without their support and advice.
"I would also like to thank my family and friends who have supported me throughout my time in Parliament."