A taxonomy of potential values conflicts in evaluations is presented. Basis is the distinction of types of conflict (aims vs. means conflicts; qualitative vs. quantitative conflicts). Six areas of values are discussed: the ethical, methodical, social and interactive, legal, economic, and personal values. The taxonomy of conflicts between these values is applied to a concrete evaluation process, namely the student rating of teaching at the University of Salzburg. Some of the conflicts are discussed, e.g. bandwidth vs. fidelity, individual vs. social and criterion oriented reference norm, student ratings vs. evaluation, and cheating teachers. It is suggested to use the taxonomy before starting an evaluation. (Contains 2 footnotes and 3 tables.)