On an example of a kind of folklore - commemorative narration, the essay is understood as a reflection on the relation of folkloristics to the methodology of multidisciplinarity, interdisciplinarity and especially to the new methodological stream - transdisciplinarity. It substantiates the folklore to reflect the social, cultural, historic, ethnographic and other 'non-folklore' phenomena in which it is performed and actualized, meeting its functions. Therefore, the relation of folkloristics to other disciplines is (and has to be) opened and its methodology is (and has to be) interdisciplinary. The main and crucial criteria for folklore analysis and interpretation cannot be substituted, however, by the methods of 'non-folklore' disciplines. The methodology of transdisciplinarity supposes such an abstracted folklore phenomenon (factum, sign), becoming a part of the problematics ruling over the interdisciplinary approach and representing its common 'keystone', to be applied across the branches. There are applied both the elements of anthropology, culturology, sociology, elements of communication etc. New professional literature is used and annotated in the analysis. The common observations are demonstrated in different versions of commemorative narration. The traditions and experience of Czech folkloristics are emphasized as well.