Access is multi-user enabled right out of the box. It is best to split the
front end (user interface, queries, forms, reports, macros, and modules)
from the back end (tables and relationships) and link to the backend tables.
If you are careful not to handle user customization by putting tables in the
front end, when it comes time for an update that doesn't require
restructuring the database (and most do not), you can just have each user
download a new copy of the updated front end, go through linking the tables,
and you're "good to go". Three sites with good multiuser information are
those of MVPs Tony Toews, Allend Browne, and former-MVP Jeff Conrad -- all
are listed, with links, on the first page of my Access user group site
http://sp.ntpcug.org/accesssig/.
You can use a split Access with Jet .MDB or ACE .ACCDB, you can link other
database's tables (e.g, dBase or FoxPro .DBF files), and you can use Access
as the client application to most server databases that are ODBC-compliant
or have an OLEDB data provider. These are some of Access strongest points.
Larry Linson
Microsoft Office Access MVP