A quick look at the published work on materials evaluation (e.g., Cunningsworth, 1984; Breen & Candlin, 1987; Skierso, 1991; McDonough & Shaw, 1993) reveals that it is almost entirely concerned with predictive evaluation. That is, it gives advice to teachers about how to conduct an evaluation of published materials in order to determine whether the materials are suitable for a given group of learners. This kind of evaluation is predictive in the sense that it seeks to determine whether materials are likely to work in a specific teaching context. Valuable as this kind of evaluation is, it is not what I am concerned with here or in the workshop I will be giving at the JALT International Conference in Hiroshima.