Generally speaking, an access project, is a client server implementation to sql server. It uses an OLEDB connection to sql server and makes it easy to bind stored procedures to Forms and Reports. So, it restricts the developer from treating sql server like a file server as can be done with an access mdb. You can achieve treating an mdb as a client to sql server by NOT linking sql server tables, instead connect through OLEDB using ADO and binding recordsets to your Forms and Reports. Since, I use access 2000, it is not easy (or as robust) to do this through an mdb. It is my understanding that with access 2002 and above it is easier to bind Forms and Reports to recordsets. Another thing, is that an adp is not multi-user, but then an mdb should not be multi-user either. So, either can work effectively, but the biggest thing is how free of access you have to the sql server environment including tools such as Query Analyzer and Enterprise Manager. If you are controlled by a restrictive DBA either access product will be more difficult than the single mdb environment.