Validation of qualitative research is here discussed in relation to postmodern conceptions of knowledge. A modernist notion of true knowledge as a mirror of reality is replaced by a postmodern understanding of knowledge as a social construction. Of the common psychometric concepts of validity, predictive validity is related to a modernist correspon dence theory of truth, whereas construct validity may be extended to encompass a social construction of reality. Three approaches to validity are outlined in some detail. First, validity is treated as an expression of craftsmanship, with an emphasis on quality of research by checking, questioning, and theorizing on the nature of the phenomena investigated. Second, by going beyond correspondence criteria of validity, the emphasis on observation is extended to include conversation about the observations, with a communicative concept of validity. Third, by discarding a modern legitimation mania, justification of knowledge is replaced by application, with a pragmatic concept of validity. In conclusion, the validity of the validity question is questioned.