Historically, charitable trusts and foundations have sought to prevent acute social problems in the UK, using grants to demonstrate and fund interventions that improve social outcomes and reduce the number of individuals requiring crisis interventions. Trust and foundation resources are limited however – only £ per year compared to government budgets of £603bn10 – enabling them to demonstrate effective interventions, but not to make them available to everyone who would benefi t. Without reliable, large- scale funding for prevention and early intervention, trusts and foundations are left to fund effective interventions, on a relatively small scale, indefi nitely. In response to this situation, Social Finance has developed a new contracting and fi nancing mechanism: the.