Flexibility is a competitive weapon in the changing environment. In order to pursue the flexibility, Korean manufacturing companies must define the flexibility dimension clearly, build the appropriate manufacturing infrastructures and measure the right flexibility performance indicators. This paper found out as follows. First, Korean manufacturing companies' flexibility strategy groups were formed three types. They are flexibility superior group, middle flexibility group and flexibility inferior group. Second, when different types of flexibility strategy group measured their performances, the degree of importance of flexibility performance indicators were different among groups. Third, when different types of flexibility strategy group were pursued, the different manufacturing methods such as product/process design technology, analysis technology, production system management technology and non technological factors were used. Lastly, when different types of flexibility strategy group were pursued, the actual flexibility performances were different among groups.