This paper deals with dynamic patterns of the longitudinal technology development and strategic changes in the Korean telecommunications equipment industry, focusing on a case of the large-scale technology development project that is known as the TDX project. The ultimate purpose of this paper is to find underlying principles in successfully managing large-scale projects or programs which involve collaborative efforts of public and private sectors in the context of developing countries. For this purpose, this paper takes a system-analytic approach to the innovation process and strategic changes. From the process perspective, it explains dynamics of the technology development process of a Korean telecommunications industry and its strategic changes along three development stages: initiation, early, and late internalization stages, From the strategy perspective, some underlying principles behind the successful technology development process are identified: the focused-and-phased, the buy-for-make, and the harmonized collaboration-and-competition approaches. Finally, implications for researchers and policy makers are discussed.