It is strong necessary for this study to extent the literature contributions for the effect of resource-based theory on e-CRM study. Based on the theory perspective, the purpose of this study is to expand and achieve a better understanding of a natural e-CRM phenomenon, namely the interaction effect of HR-service capability, IT-service capability, and KM-servilce capability on its e-CRM process to the performance. A total of 300 questionnaires were distributed in the summer of 2006 to four Taiwanese banks, which have applied the e-CRM system to their customer service operations. Multiple hierarchical/interaction regressions were applied to the results, and it was discovered that when an institution uses e-CRM services with web-based applications to establish and raise the combination levels of HR-service capability, IT-service capability, and MK-service capability, these conjoint effects resulted in a favorable interaction relationship and thus can help the institution achieve the so-called "profit-maximizing portfolio" level. Excluding interaction effect among these three service assets will lead to inaccurate prediction of its e-CRM performance.