The use of these leaderhip concepts are often presented in terms of normative assumptions of successful leadership. This leads to the question about how successful school leadership - the success of school leaders - should be measured. The aim of the third paper is to investigate how the performance of school leaders is operationalised in scientific studies and what measurements are used to assess the performance of school principals in the field of research? In this mapping exercise, empirical studies are coded according to the following a priori categories: year, country, school type, number of performance measurements, kind of measurement (e.g. questionnaire, observation), focus of the measurement (e.g. outcome, behaviour, trait), source of evaluation (principal itself, teachers, parents, school administrators) etc. Moreover, the paper includes a discussion related to the usefulness of indicators and performance measurements used in empirical studies related to methodological aspects as well as practical implications. At last the paper presents suggestions for future operationalisations of performance measurements.