>I am re-writing a VFP app to work in strict Client/Server mode where the server could be VFP, Oracle or SQL Sever which may even be on a Internet site.
>I am considering writing 3 wrapper functions that will handle the Server read/write and each of these functions will have some CASE statements based on the backend in use.
>The 3 functions are Connect2Dbc, ReadSQL and WriteSQL. Is there an engine of this nature currently available ? If not what technology will be best - ADO, MTS or Remote Views

MTS is not a data access technology, but it is a great place to host your middle-tier COM servers. Remote views can't be passed between tiers. That leaves ADO. There was a recent discussion here on this. Look for the thread "VB vs. VFP" and thread #284987, "ADO Management Class".