Thank you Duane for your help! I added the reference and I no longer get the "User-defined type not defined" error.
Now, when I try to run the following code, I get the "Run time error 13, Type mismatch" message on the last line.
Dim rs As Recordset
Dim qdf As QueryDef
Set qdf = CurrentDb.QueryDefs("MyQuery")
qdf.Parameters("Project ID") = strProjID
Set rs = qdf.OpenRecordset()
Please help!
SJH