Thanks for your reply.

I had looked through ASK TOM before I posted the question.

He does answer one like this unfortunately he just directs the guy to a technet document explaining dbms_obfuscation_toolkit.

While this is useful in understanding the concept, the example given is to encrypt single strings not entire columns (I think that's what it's doing).

I'm a novice in PL/SQL and am finding it hard recode this example.

Regards

Alison