While educational science considers social competence as a basic and important outcome of education received in family and education institutions, there is not much empirical research in this area yet. Regarding the construct of social competence, several attempts have been made to clarify the concept – all of them underlining the multidimensional and multi-facet nature of the construct. This is reflected by the empirical research methods and study designs employed in the field. Modeling social competence often uses multivariate measures based on questionnaire data and multi-informant assessments put together in sophisticated structural equation models. The symposium brings together four research groups analyzing the social competence in three different European countries all using questionnaire data. The symposium provides for a broad picture on how defining and assessing the concept in different age groups, by different informants, and by multiple points in time regarding different validation criteria that range from construct validity to measures of success in education, and extends to indicators of socio-emotional well-being and mental health. The complex nature of the construct of social competence could be supposed to be one difficulty for its empirical analysis. Social competence is described as the ability to effectively make and maintain positive social outcomes by organizing one’s own personal and environmental resources. Most frequently cited is the Rubin and Rose-Krasnor (1992) definition: Social competence is “the ability to achieve personal goals in social interaction while simultaneously maintaining positive relationships with others over time and across situations”. There are different assessment strategies to reflect the interactive nature of the construct. Concerning the design of the study one least demanding strategy is to capture measures of self-perceived social relations. This could be extended by assessing the social relatedness of the focused child or adolescent: members of the prominent groups he or she is a member of are asked to give ratings on the focused person. In most cases these groups will be classes in schools or groups in early child care. Therefore studies must be placed within the nested structure of education systems with the need of assessing all group members which is the case for sociometric methods. . Data analysis for nested designs must refer to multilevel modeling. Using multi-informant assessments leads to the consequence of either conceiving two or three or even more (e.g., self-assessment, teacher rating, parent rating; also peer rating, external expert rating) dependent variables that simultaneously are to be analyzed in a MANOVA framework or of integrating mediating and effect variables in structural equation models (SEM).