Complexity theory brings new challenges and opportunities to better test and harness software for its intended purposes. The software spectrum spans from the unit to massively indeterminate systems of interactive systems. Software integration testing has been traditionally problematic for a number of reasons. Evidence grows that embedded software exhibits scale-free network characteristics. Complexity is borne from the interaction among software modules operating in a networked environment. Networked software components interact non-deterministically to generate a holistic behavior patterns. Nonetheless, a robust research agenda is available for applied systems integration testing. The design and deployment of software must be considered a part of the greater whole and no longer an end onto itself. To do so, means holistic thinking at unprecedented levels.