This paper outlines a novel general framework for analysing energy diversity. A critical review of different reasons for policy interest reveals that diversity is more than a supply security strategy. There are particular synergies with strategies for transitions to sustainability. Yet despite much important work policy analysis tends to address only a subset of the properties of diversity and remains subject to ambiguity, neglect and special pleading. Developing earlier work, the paper proposes a more comprehensive heuristic framework, accommodating a wide range of different disciplinary and socio-political perspectives. It is argued that the associated multicriteria diversity analysis method provides a more systematic, complete and transparent way to articulate disparate perspectives and approaches and so help to inform more robust and accountable policymaking.