¡§People¡¨ is the key to a company¡¦s success, as all processes from R&D, sales to services were handled by people. Therefore, quality of a team determines whether a company will be successful or not, and this is exactly why companies starting to pay increasing attention to ¡§core competency¡¨. Technology, products and services can easily be duplicated, but employees are the only, and most important, assets in a company that can not be replaced. Excellence employees will lead to the competitiveness and profitability of a company and are the foundation of successful companies. It is an imperative for modern companies to cultivate employees¡¦ ¡§core competency¡¨ so that companies can reasonably leverage, motivate and accumulate top quality human assets in order to reach maximum productivity and support the actualization of operation strategy. This study aims at using case study of a software development company of high tech industry to understand the construction of the core competency model and its process. Through literature review, focus groups and executive interviews, the study comes up with the core competency of all employees and the managerial core competency of managers. The study hopes to be able to help other industries to introduce their core competency so as to increase the overall organizational efficiency. Core competency means the knowledge, skills, behaviors and traits that employees need in order for a company to actualize its operation strategy. Therefore, the mid- to long-term business strategy is the base of the development of core competency. The 5 core competencies in the study were developed based on the following factors: company mission and vision, 3 year strategies and goals, unique competitive advantages, key successful factors and the benchmarking of other model companies. Each core competency must have very clear definition and description of its corresponding behaviors of the contribution and impact for various levels of employees. The definition and behaviors descriptions serve as the base for the company¡¦s core competency evaluation and also set the future direction for the company. This study results showed that the company, after introducing core competency system, was able to understand precisely the core competency gap between its individual manager and the team average. The study also demonstrated the fact that the individual manager¡¦s core competency improved visibly in a year through training on the targeted core competencies. This study validated that the organizational efficiency can be increased by the constructing of core competency system and the implementation of the performance management system.