The use of deliberative methods to assess environmental values in monetary terms has been motivated by the potential for small group discussion to help with preference formation and the inclusion of non-economic values. In this review, two broad approaches are identified: preference economisation and preference moralisation. The former is analytical, concentrates upon issues of poor respondent cognition and produces a narrow conception of value linked to utilitarianism. The latter emphasises political legitimacy, appeals to community values and tends to privilege arguments made in the public interest. Both approaches are shown to embrace forms of value convergence, which undermine the prospects for value pluralism. As a result exclusion and predefinition of values dominates current practice. In order to maintain democratic credentials, the importance attributed to monetary value needs to be left as an open question to be addressed as part of a process determining an “agreement to pay”. To this end we identify a discourse-based approach as a third way consistent with the democratic and value plural potential of deliberative monetary valuation.