Former City minister Lord Myners wants to replace this with a slimmed-down "plc and beyond" structure staffed by professionally-trained directors.
The former Marks & Spencer boss was appointed a director of the Co-operative Group in December but announced he is to leave following this weekend's vote.
He has said it was apparent to him from the first time he attended a board meeting that not one of its members had the ability to address the complex issues faced by a group burdened with £1.4 billion of debt.
This weekend's ballot will be decided by representatives of its independent societies and affiliated organisations - who hold 22% of the vote - and others voting on behalf of its regional membership boards making up the remaining 78%.
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The brother of British holidaymaker Steven Cook who vanished in Crete 10 years ago has his family are "sure he's alive".
Neurologist and author Dr Oliver Sacks CBE who wrote popular case histories like “The Man Who Mistook His Wife for a Hat", has died aged 82.