Abstract: The external view of sustained competitive advantage is based on the assumption of homogeneity of firm,that is to say the firm is looked as a black box.Resource based view hold a assumption of heterogeneity.Because of the misleading of some essential concept such as the resource and focusing on the conditionals of SCA,the theory made a weakness is called black box on process that affect the theory’s development and application at management.This paper will divide competence from the resource,gives a new viewpoint about strategy based on the competence theory,embodies the framework of resource strategy performance,and finally develops a process orientation model about the causal chain of sustained competitive advantage.

Key words: sustained competitive advantage, causal chain, resource, core competence