In a computer system having hierarchically-arranged data storage apparatuses, a management computer provides information required for performing operation on the data storage apparatuses.Through a network for collecting management information, storage area information and hierarchy information are collected from each data storage apparatus. Management relation information is created using the collected storage area information and the collected hierarchy information together with programs for respectively managing the data storage apparatuses, and, the created management relation information is held. Based on the created management relation information, a display screen expressing the hierarchy of the data storage apparatuses is created. Further, responding to operation by a user, a return considering the hierarchy is displayed.