  Current extragalactic databases are reviewed, including object-oriented
databases, astronomical catalogues and compilations, as well as image archives
and object catalogues from large-scale surveys. One challenge of the future
will be to maintain the accessibility of all published information on
individual objects; the other will be the cross-identification between various
ongoing and planned large-scale surveys, some of them resulting in several
hundred million objects each. Powerful user interfaces are being developed to
tackle these tasks.
