This Christian charity was founded in 1997 by Paddy and Carol Henderson to help street children in Romania, using a legacy from Carol's mother, Betty Trussell. Its work was extended to the UK and in 2000 it opened its first food bank in Salisbury, Wiltshire, operating out of the Hendersons' garage and shed.
A countrywide network was launched in 2004: there are now 345 such food banks, and three new ones are started each week in partnership with churches and community groups. Food is donated by schools, churches, businesses and supermarket shoppers, who are asked to buy and give one or two extra items. Care professionals offer vouchers to people in need who redeem them for three days' food.
The charity also runs community enterprises, ranging from eight charity shops and a recycling centre to a supported volunteer programme for people with mental, social, learning and physical difficulties.
Its operations have also grown in Bulgaria, where it runs the House of Opportunity programme, which works to help orphanage leavers to stay away from crime, prostitution and drug abuse.
In its mission and vision statement, the trust says: "We believe that everyone has the right to have food on their plate, dignity, skills, a chance to work and hope for the future."
Nearly 350,000 people in the UK were helped by the trust in 2011/12 - nearly three times as many as in the previous year. Its executive chair, Chris Mould, calls this "a wake-up call to the nation".
This award is for the charity, voluntary organisation or social enterprise that has attracted the admiration of others in the sector for its recent achievements. These might include: success in its objectives; giving outstanding service to beneficiaries; effectiveness in pursuing a change in the law, public policy or social attitudes; carving out a distinctive position and voice for itself; or being particularly well managed or governed.
For 30 years, WaterAid has worked with local partners in the developing world to provide clean water and safe sanitation, and to influence decision-makers. With an income of nearly £56m last year, it helped 1.6 million people get access to safe water in 27 countries, mostly in Africa and the Indian subcontinent.
The charity believes that economic development is dependent on clean water and sanitation, without which millions of people are trapped in a cycle of poverty and disease. "Across the developing world, millions of women are wasting time collecting dirty water, children are dying from preventable diarrhoeal diseases and communities have open sewers running through them," the charity says on its website.
One nominator said WaterAid was "a charity that has expanded and refreshed itself recently and run great campaigns, ramming home, for example, the fact that more people die of bad sanitation than of malaria". Another admired the way it "manages to keep its agenda at the front of the public's conscience - it continues to get great support for a simple life-giving cause".
THIRD PLACE: ALZHEIMER'S SOCIETY
The Alzheimer's Society was founded in 1979 and its income has grown steadily from £31m in 2004 to £71m in 2012. Led by Jeremy Hughes, its most notable current project is Dementia Friends, which has received £2.4m from the Department of Health and the Office for Civil Society to recruit a million volunteers by 2015 to support people suffering from dementia. One nominator called this "a hugely impressive level of engagement with government". Another said: "The Alzheimer's Society has come of age in terms of service provision, advocacy and fundraising, and this has been the result of a clear strategic focus."
Also shortlisted - Prostate Cancer UK, Save the Children, Teach First.