Today many disciplines including organization and management, public administration, social psychology, educational research and political science are becoming interested in dialogue. Evaluators are only just beginning to recognize how valuable dialogue can be for their work. Dialogue may have the potential to improve the democratic quality of decision making and judgement in postmodern societies and enhance (mutual) understanding between people. In this special issue we aim to disentangle some of the complexities, meanings and aims of dialogue and dialogical evaluation. A number of evaluation scholars and practitioners will discuss different notions of the concept and its relevance for evaluation practice. They will also deal with some practical considerations: what are the essential characteristics of evaluation dialogue; who should participate and what should the role and responsibility of evaluators be. We will also identify areas where we think caution should be exercised. Examples of dialogical evaluation projects in various policy settings and countries – including Sweden, Holland and the USA – together with comments by other scholars are meant to stimulate an exchange of ideas.