Share a field between tables.

I am looking it up now. It looks like it will work for what I need to do. I will let you know. Thanks!

So if I am understanding this correctly, I must first combine the two like fields across tables with a report link or parent child relationship. Once I have that in place, I can use an action between them. Does that sound right?

You combine the two fields via a report link field. Create the report link field in the table where the unique field is populated. Both tables must have a unique identifier. That's the only way you can match record to record. For example, Table 1 Record ID matches exact with Table 2 Record ID.
When you set up the report link field, select the field in the table that matches exact to the field in the target table. Now you can use it in the action. There's no need to create a relationship to have a report link field.
Hope that makes sense.