We provide different courses for many clients, we found a problem for hierarchical organization for our courses. For each client we have a different categories of courses. In a category we have different courses, each course have a different tutor and there is a general tutor for each client (a category tutor). For us, it's important that a "student" could see only the courses of his category, he can search other courses only in his category and when he logs, the first page has specific information of his category. Although is also important having a single platform for all our clients, so for our administrators it's easy the maintenance of Moodle, so we don't want a Moodle istance for each client. Is someone interested in our development? Is someone developing something like this?