Thanks for this article! Just to be clear the DirectAccess function above is getting the VehicleRegistration at the Index of the Vehicle loop that matches the index of the Trip loop as it goes through that loop. It's not somehow matching the VehicleID from Trips loop to the Vehicle loop. So this would require the Vehicle loop to have the same number or greater of items as the Trips loop. I think the DirectAccess function may help with want I'm trying to do, which is to take values from a loop in the source schema and flatten them to be used in the destination schema. Maybe to either take the first trip from a loop or the trip info for a specific VehicleID (to use the example here). I've been trying to make something like this work in the Data Mapper and haven't been successful yet. Any guidance would be most appreciated. These articles discussing the Data Mapper capabilities and functions are great. Keep them coming!