The Co-operative is to set new targets for increasing the number of women on its boards under moves to make them more representative of the communities they serve.
The company published an Ethical Plan, including a commitment to make sure that 40% of its Group and Bank boards will be made up of women by 2018.
The main board of the Co-op, which runs food, banking, insurance, funeral care, pharmacy, legal and online electrical businesses, has been 25% female for the past two years.
Composition of the firm's 48 area committees, which enable members to have a say in the running of the business, will become more representative of local communities by 2014.
Group chairman Len Wardle said: "We want to be the most socially responsible business in the UK and our latest Ethical Plan sets out our intention to improve the diversity of our governance structure.
"These are difficult targets and we have far to go, but our businesses operate in communities across the UK so it is essential that we work even harder to ensure that our governance structure represents them."
The Co-op also unveiled plans to provide an additional £1 million of support to co-operative enterprises, and increase reduction in greenhouse gas emissions from its operations.