In many application scenarios the database is changing quite rapidly. Because the management of such data is rather expensive and cumbersome, many applications like data warehouses only store some aggregations of it. We describe a strategy how the evolution of object databases can be controlled by enhanced versioning. Therefore, we extend the notions of ODMG in order to capture temporal versions. We analyze the consequences for the consistency notions and the semantics of queries. Moreover, we sketch a framework how these concepts can be implemented.