There is a growing recognition that citizens should play a role in informing and shaping environmental policy. But how should this be done? This paper explores one route, where opportunities 'from above' are created, often, but not exclusively so, by the state, often through local government policy and planning processes. A set of approaches - known collectively as Deliberative Inclusionary Processes (DIPs) - are explored in different settings through 35 case studies from both the north and south. These experiments in more inclusive, participatory forms of policy deliberation have been prompted by a number of factors. These include wider political shifts towards new forms of citizenship and democracy; concerns about policy effectiveness and implementation success; the emerging recognition of the complexity and uncertainty inherent in environmental problems; growing levels of distrust in policy processes and expert institutions; and the increasingly recognised importance of accepting that values, ethics and issues of justice are key to environmental policy problems. Through an examination of lessons emerging from the case studies, practical issues, such as time and resource constraints, are considered alongside methodological questions emerging from asking: who convenes the process, who defines the questions, and how are multiple forms of expertise accommodated? The paper shows how power relations and institutional contexts critically affect the outcomes of DIPs processes. Without linking such processes to broader processes of policy change - including connections to conventional forms of democratic representation - DIPs may simply be one-off events, and so their considerable potentials for transforming environmental policy processes will go unrealised.