Sorry for the confusion: I'm talking about integration tests.  

I'd like to test the logic of a BPL that makes calls to multiple external application. I'll create my mockup services in SoapUI and will try to run multiple scenarios.  

Thanks for the advice.

Thanks Derek. I've been through the tutorial already but it shows how to test HL7 Routing rules + DTL or business operations that are not connected to an external system. 

I'd like to be able to test a BPL that do sync and async calls to a downstream system I don't have access to. So in order to test the BPL, I'll need to simulate some responses from the business operation. So I'll probably need to create some kind of mock service/operation maybe using a second production...