He and others in the "Notting Hill set" have sought to focus on issues such as the environment, work-life balance and international development – issues not previously seen as priorities for the post-Thatcher Conservative party. In a speech to the Conservative annual conference in October 2006, he identified the concept of "social responsibility" as the essence of his political philosophy. The idea of the Big Society, championed by Cameron under the 2010 coalition government, proposes "integrating the free market with a theory of social solidarity based on hierarchy and voluntarism" drawing upon "a mix of conservative communitarianism and libertarian paternalism" in principle.