[en] This report presents the main features of the Josef Stefan Institute work in the course of the year 1986. The research projects and activities of the Institute are described in detail in the following fields: physics (theoretical, nuclear, solid state and reactor physics), chemistry (nuclear, physical, analytical, high temperature, fluorine chemistry, ceramics and biochemistry), electronics (automation, biocybernetics, robotics, computer science and information science, energy and process control and professional electronics), reactor engineering and safety, and applied mathematics and many interdisciplinary projects resulting from these fields. Special attention is paid to those fields and programmes which are important to the growth and development of the national economy. In addition, the operational structure of the Institute and its budget are also mentioned. The document contains a list of the project titles which the Institute coordinates. There is another list of printed material (journal articles, thesis, conference papers, etc.) written by researchers of the Institute. (Z.Z.). 1143 refs