When the Intranet and Extranet are raised, and the application of Electronic Commerce are demanded increasingly, the Directory Services have been become important infrastructure for many enterprises. The objective of this paper is to provide a mechanism and some useful methods for integrating directories in enterprise. With this mechanism, all resource in enterprise can be managed in a unified manner and the total ROI of enterprise will be much higher. The mechanism adopts Meta-directory for implementation, which connects many directories appropriately by Join-engine and Connector. We proposed two methods that include Password-Synchronous Method and Object-Join Method on this mechanism to improve the benefits. Finally, an example of ITRJ Directory Services is implemented to prove the accuracy of these methods. This result of this paper has following benefits: (1) The information window is unifying and integrating. (2) The information applications environment was securable. (3) It has unified policies and distributed management.