The papers in this special issue investigate a range of topics that pertain to the distinction between the concept and the property of truth. The distinction between property concepts and the properties that they pick out is a mainstay within analytic philosophy. We have learned to distinguish, for instance, between our ordinary concept SIMULTANEOUS and the property simultaneity that it picks out.Footnote1 The significance of this distinction is borne out in the theories of reference that were developed, for instance, by Putnam (1975), Kripke (1980), and Lewis (1984). If we apply any of these theories to SIMULTANEOUS, they will generate the result that this concept refers to the relativized property simultaneity, even if many users of the concept take simultaneity to be absolute.