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of MPs holding a debate on co-operatives and mutuality in the economy from 2.30pm on 30 June 2011.
Mutual institutions are owned by, and run for, the benefit of their members.
In the UK, building societies were set up as mutual organisations offering financial services more than 200 years ago.
There are currently nearly 50 building societies across the country.
In contrast, banks are usually companies listed on the stock exchange, and run for their shareholders.
A recent report by the trade body Co-operatives UK recommended the mutualisation of the Post Office.
It said a hybrid between employee-owned mutuals such as John Lewis and customer-owned mutuals like the Co-operative Group would work best for the Post Office.
The report recommended that employees and subpostmasters, as well as representatives of customers, including consumers, charities and community groups, should be allowed to become members.
The government says a mutual Post Office is a "realistic proposition" by 2015.
The debate is being led by Labour MPs Chris Evans and Adrian Bailey.