I have a lookup field which does the lookup just fine. However, if I modify the looked-up value in the destination file, it also changes the value in the source file. Can I prevent this? The lookup is for a price. I want the price to be looked up; if I subsequently change the price field in either the source or destination file, I do not want it to modify the other. Thanks.

It sounds like you're using a related field rather than a lookup. When you look at the field in layout mode on the layout, does it begin with "::"?

If so, the this is a related field, and changing it will change its value in the related database.

Create a field in your local database called Price. Set it to be a number field. Click on the Options for the field and choose Looked-up value. Select your relationship from the menu in the top right and you will see a list of fields in the related database. Select the price field and click OK and then OK again.

You'll probably have to perform a re-lookup for your existing data. Do this by going to a layout that has the local field the relationship is based on (or create one if it isn't on any layout), click into the field, and choose Relookup from the Records menu. This will populate the price field for you.

Chuck