The document discusses the UK Supplier Obligation policy for improving home energy efficiency. It describes how the Carbon Emissions Reduction Target (CERT) scheme works, requiring energy suppliers to meet targets by subsidizing insulation and other energy efficiency measures. CERT has helped insulate over 3 million households since 2008 and is estimated to save £22 billion by reducing carbon emissions. A new Energy Company Obligation (ECO) will replace CERT after 2012, building on its successes and integrating with the new Green Deal financing program to focus on hard to treat homes and vulnerable consumers.