Some systems interact with their environment at a number of physically distributed interfaces/ports and when testing such a system it is normal to place a local tester at each port. If the local testers cannot interact with one another and there is no global clock then we are testing in the distributed test architecture and this can introduce additional controllability and observability problems. While there has been interest in test generation algorithms that overcome controllability and observability problems, such algorithms lack generality since controllability and observability problems cannot always be overcome. In addition, traditionally only deterministic systems and models have been considered despite distributed systems often being non-deterministic. This paper describes recent work that characterized the power of testing in the distributed test architecture in the context of testing from a deterministic finite state machine and also work that investigated testing from a non-deterministic finite state machine and testing from an input output transition system. This work has the potential to lead to more general test generation algorithms for the distributed test architecture.