Lithuania, as a small country, cannot afford creating new knowledge in all the fields of science. It is reasonable to firstly focus on those fields in which Lithuania already has scientific and industrial potential and that clearly declare the biggest demand for innovations as well as capability to invest into innovations. Research institutions here usually focus on fundamental research but both the revenues and the human resources of research institutions are rather poor. Dispersion of the Lithuanian potential of science and studies and the absence of critical mass represent the main reasons why R&D lacks effectiveness. The paper presents the main research fields and high-tech research institutions in Lithuania.