The directory is like many other information services in that the long term maintenance costs will probably outweigh the initial effort. Much can be done to reduce maintenance overhead by considering the issue at an early stage. Formalizing the requirement early on will be helpful. How up to date does the directory have to be How tolerant to short term errors are you If tolerance is low then procedures for management of the database should be defined well before the directory is in operation. Consider the purchase of dedicated tools for synchronization of the directory with source databases. A good synchronization utility will be able to detect changes in a source database and make those changes to the directory. The aim here is to avoid regular complete downloads of the master database into the directory, as this could have a negative affect on service performance. A management interface for manual update of the data will also be useful. Such a tool should exist for administrators to make small changes to the directory, e.g. a change of telephone number when a person moves office.