From Social Enterprise UK:
Social enterprises are businesses trading for social and environmental purposes. There are 62,000 of them in the UK, contributing over £24bn to the economy, employing approximately 800,000 people (2005-2007 data from the Annual Survey of Small Business UK).
As with all businesses, they compete to deliver goods and services. The difference is that social purpose is at the very heart of what they do, and the profits they make are reinvested towards achieving that purpose. Well known examples of social enterprises include The Big Issue, Jamie Oliver’s restaurant Fifteen, and the fair-trade chocolate company Divine Chocolate.
The government defines social enterprises as “businesses with primarily social objectives whose surpluses are principally reinvested for that purpose in the business or in the community, rather than being driven by the need to maximise profit for shareholders and owners.”
Social enterprises operate in almost every industry in the UK, from health and social care to renewable energy, from retail to recycling,from employment to sport, from housing to education.
For more information have a look at this document from the Social Enterprise UK explaining social enterprises: View Document
Also, take a look at the Social Enterprise Mark – the only certification authority for social enterprises. Their website is: www.socialenterprisemark.org.uk and includes details on the six criteria your business needs to pass to gain the Social Enterprise Mark.