Access or Full SQL Database?

I am working on a project and I know a database is the best tool for the job. But now I am wondering out of the options is Access the best option or should set up an SQL server.
Details aside, I am wondering when would you suggest making the leap from using Access to a SQL Database?
Anticipated users: Few, less than 10.
Anticipated data: Alphanumeric, no images or documents.
Anticipated amount of data: a couple dozen new records entered per day. Old records not updated once entered.
I have a feeling that Access will be more than enough for our needs, but seeing as this will be a constantly growing data set I am wondering where Access's abilities may be outstriped by our needs.
Thanks!

PatientFusion