Knowledge is becoming the source of exclusivity and a feature of uniqueness. Each organisation attempts to share relevant information at the right time and through the most convenient means to meet the needs of its clients and employees. When modernising the Lithuanian National Defence System, the need for qualified personnel able to share specific knowledge has been identified. In this sense, this paper aims to analyse the factors that influence sharing process in the Lithuanian National Defence System most, enhancing its efficiency. In order to determine and assess these factors, expert evaluation and multiple criteria assessment methods have been applied. The results show that scientists interpret factors influencing the efficiency of knowledge sharing process differently. The primary list of factors influencing the efficiency of knowledge sharing process was carried out of more than 60 factors, which were divided into three groups: individual, organisational and technological factors. In summary, individual and organisational factors are more significant to the efficiency of process compared to technological factors. Significant factors in the group of individual factors were benefits of the knowledge sharing perceived by employees, their practical experience and communication skills. Significant factors in the group of organisational factors influencing the process of efficiency were mechanisms of the employees' assessment, personnel fluctuation and its dynamic and influence on the process of knowledge sharing.Significant factors in the group of technical factors were adaptation of information technologies and possibilities of knowledge sharing process, visit to the database and accessibility of information technologies.