Using practice theory inspired approaches to mentoring, such as peer-group mentoring and “Paedeia Café”, has implications for evaluating such mentoring practices. Using summative forms of evaluation, aiming at measuring the degree to which specific, pre-determined goals are realized by using specific means, is based on the assumption, that it makes sense talking about goals and means irrespective of local context. Formative forms of evaluation, it is suggested, are more in line with the practice theory and constructivist inspired approaches underlying PGM. But seeing evaluation as part of the practice being evaluated rises questions such as: How should PGM sessions be done in order ensure the necessary critical distance, that allows for the up-take of realizations and observations, realized during mentoring sessions? What would be the special points of attention of both mentors and mentees in regard to incorporating such observations and realizations in the continuous process of professional development? Though formative forms of self-evaluations seem to be the obvious choice seen from an in-side perspective, that is from the point of view of those involved in peer group mentoring, out-side stakeholders might, from a cost-benefit point of view, have a legitimate interest in favoring summative forms of evaluation.