The WASS-ICO PhD course on Competence Theory and Research is running. The course shows that competence theory is well developed and that certain competence research is very advanced. Complex research designs and statistical analysis techniques, using detailed competence measurement and differentiated performance assessment, showed relationships between competence and performance at aggregated and desaggregated levels. Of course many of the existing studies are criticised for conceptual unclarity, inconsistent conceptualisations, limited operationalisations, weak designs and restricted analyses. Ways to improve competence theory and research are shared.