Discusses the general quality demands that should be placed on measurement procedures designed specifically for the assessment of competencies. In particular, basic concepts and basic questions of assessment in education, where the focus of assessment lies on the measurement of competencies, are introduced. Definitions for the terms assessment, test, scale, subscale, task, and item are provided. Objectivity, reliability, and validity are introduced and discussed in terms of their specific relevance to evaluating the psychometric quality of competence oriented tests. Also discusses critical questions regarding the development of measurement instruments for competencies. In conclusion, a brief overview is given of the functions and possible specifications of the different psychometric models that can be applied to evaluate test data and to draw conclusions about the competencies of the tested individuals.