We investigate the prospects of voluntary ecological sufficiency for environmental and climate policy under the constraints implied by political liberalism. We find that freedom of choice restricts sufficiency to rather wealthy societies and that a sufficiency threshold cannot be derived by referring to the poor. Sufficiency can be in conflict with the demands of social justice, i.e. if the sufficiency threshold is below the social minimum implied by social justice. Benefits from sufficiency are highly related to individual perceptions. Such benefits cannot be expressed in a standard preference framework. Consequently, alternative measures of welfare and inequality are required if sufficiency is a significant phenomenon in society. 'Standard' environmental policies can have a pronounced interaction with voluntary sufficiency, i.e. if 'quantity regulation' is present. Overall, the voluntary notion of sufficiency causes a dilemma as sufficiency is largely a matter of civil society. However, voluntary sufficiency is expected to make important contributions to the preservation of ecological resources if properly balanced with social and environmental policies and framed by public discursive control.