Here is exactly the same example as for Reporting Services:

- reading Region codes from IATI master data

- using it as a parameter to load DFID file for the related region

- showing the description of every related activities

This sample uses Infopath 2007: IATI.xsn file attached, save it locally, right-click and choose 'Design' (you need to have Infopath on your machine), then you can preview or publish it in your environment.

It also uses 5 C# lines of code to use the region as a parameter (well... 8 lines if we count the 'try...catch'). 

Fred