Implementing the Three Lines Model Through Governance Platforms
How evolving roles, feedback loops, and adaptive technology bring the model to life
The debate around the Three Lines of Defense model has heated up again. Just last week, the GRC Engineer newsletter featured an article by Ayoub Fandi called “The Three Lines of Defense, a systems-thinking approach”. His central argument: the original model creates rigid silos and operational blind spots, but rather than throw it away, we should add feedback loops that connect security (1st line), GRC (2nd line), and audit (3rd line) into an adaptive system.
Ayoub makes a compelling case. He points out that without shared visibility, each line optimizes locally — security designs controls, GRC tests compliance, audit reports findings — but the system as a whole doesn’t actually reduce risk effectively. The missing ingredient, he says, is feedback loops: unified dashboards, outcome-based KPIs, and collaborative incident response. With those in place, governance shifts from rigid silos to an adaptive system optimized for enterprise-wide outcomes.
That made us reflect on two things: first, our own article “Implementing Cyber Governance Across Enterprise Stakeholders”, where we argued that governance breaks down when each stakeholder group operates on its own tools and timelines. And second, the fact that in 2020 the Institute of Internal Auditors formally updated the “Three Lines of Defense Model” to the “Three Lines Model” in order to emphasize collaboration, value creation, and alignment over rigid lines of defense.
When you look at all three together — the IIA’s updated principles, Ayoub’s systems-thinking recommendations, and the operational realities we described — the picture is clear: the future of governance isn’t about defense in silos, it’s about governance as a system. A system that aligns roles, creates feedback loops, and is enabled by platforms that unify data, controls, and frameworks across the enterprise.
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Building Governance Like a Tree
Both the IIA’s updated model and Ayoub’s systems-thinking approach emphasize that governance is not a one-time design exercise. Each enterprise has a unique distribution of responsibilities, and these evolve over time. That means building effective governance is less like assembling a machine and more like cultivating a tree: you start small, nurture it deliberately, and allow it to grow into something balanced and sustainable.
We’ve written about this before in our Tree Metaphor series (“The Best Time to Start With a Governance Platform Is Now” and “Buying a Governance Platform? Here’s How to Build the Strategy Before the Purchase — and Set It Up for Success”), and the parallels are clear.
This has two implications:
Pick a starting point. Like Ayoub suggests (beginning with one control family) and as the IIA notes (roles may be blended or distributed differently at first), you don’t have to implement the entire model at once. Start with a single domain — access control, data protection, vendor risk — and build shared visibility there.
Implement with roles in mind. A governance platform is not a magic switch. To succeed, it has to reflect your internal Three Lines Model: who is responsible, who executes, who supports, and who is informed. ABAC/RBAC access controls can encode these distinctions, but only if you’ve clarified them first. If you simply “say yes” to the model and then hand ownership to one team, you recreate the same silo problems the model was designed to avoid.
In other words: building governance is about starting small and building deliberately — but with the system-level design in mind from day one.
Closing Thoughts
When you line these perspectives up, a clear through-line emerges.
The IIA’s Three Lines Model (2020) defines the principles and clarifies roles, while emphasizing that responsibilities are unique to each enterprise and evolve over time.
Ayoub Fandi’s systems-thinking approach highlights the missing ingredient: feedback loops that connect those roles into a dynamic, adaptive system.
And a well-designed governance platform makes both achievable in practice — aligning responsibilities through ABAC/RBAC and R.A.C.I.. This means that ops, security, compliance, and internal audit can all run their priorities concurrently — without creating reconciliation work or layering on new tools as tech evolves. One stakeholder no longer has to watch their priorities take a backseat to another stakeholder’s priorities. The only things they may have to give up are silos, redundant tools, manual reconciliation work, out-of-date reporting, and a whole lot of frustration.
This turns governance from static defense into an adaptive system that creates value: fewer redundant tickets, faster remediation, stronger assurance, and a common language for every stakeholder.
In short: the model has evolved, practitioners are asking for systems thinking, and governance platforms are the way to make it real at enterprise scale.