Emphasis in recent years has been placed on control testing to ensure controls are working effectively and efficiently, but emerging thought leadership indicates that the internal audit value proposition can best be accomplished through internal audit consulting services. The term, "trusted Advisor" is being used more frequently to describe internal auditors as they strive to add additional value as they gain management's confidence through the impactful consulting services they provide.

Perform research and identify alternative model(s) of assurance layering other than the "three lines of defense model." Prepare a 2-3 page report comparing and contrasting the(se) models. How do they differ? How are they similar?