The purpose of this study is to identify the influential factors and their impacts with the multi-factor analysis in the choice of technology acquisition mode. Although this area has already been studied, some limitations are found in most of the previous studies. Their research was based on one or a few factors and/or under the conditions of ceteris paribus for the appropriate mode. Hence, this study suggests an integrated framework within which various internal and external factors (characteristics of a firm, its needed technology, and external environments) can be studied. And then questionnaire returns from the small and medium size firms in the Korean telecommunication industry are analyzed, primarily using multiple discriminant analysis to distinguish among three modes of the firms' R&D involvement (In-house R&D, R&D cooperation and Technology purchasing). The results show that the significant discriminant factors are found in each characteristics and that historical pattern of the choice of mode is the most significant factor between In-house R&D and other modes, and accumulated technological capability between R&D cooperation and Technology purchasing. Finally, we present a discussion of the meanings of results and conclusions with implications. (C) 2000 Published by Elsevier Science Ltd.