Objective. A study is reported of the perceptions of the Slovenian library practitioners of the competencies needed for their work today and will be needed in the future. Two groups of competencies were considered: generic and professional, the latter in four groups: library management and library operations, library materials and information resources, work with users, organization of knowledge and information. Approach/Methodology/Design. Online survey was used. To cover practitioners in all types and sizes of libraries, random sampling of libraries was used and snowball sampling from there on (N = 132). We discuss the general overview of the results through descriptive statistics, and the differences in the perception of competency importance between the current and the future situation, using paired samples T-test. Results. Results show that competencies, in all groups, were rated high, for both today and future work, no criticism was detected over the choice of the competencies, only certain suggestions, the practitioners believe that nearly all competencies will gain importance in the future, and none will become less important. The highest valued area is work with users, followed by the areas of work with library materials and resources, and library management, while organization of knowledge and information was, surprisingly, rated the lowest. Practical implications. The results will be used in the formation of at least a draft competency model or models and to inform further work on the reformed study programme at the Department of LIS & BS at the University of Ljubljana.