Teams should start by identifying the critical business functions, systems, and data flows that must keep operating during disruption. DORA is built around proportionality, so the goal is not blanket protection. Security leaders should align controls, segmentation, incident response, and testing to the most important services first, then extend coverage based on operational impact and regulatory risk.
Why proportionality is the right way to read DORA
DORA is not asking financial services teams to raise every system to the same protection level. It is asking them to understand which services, data paths, and dependencies create the greatest operational impact if they fail, then apply stronger controls where disruption would matter most. That means the starting point is business criticality, not uniform technical hardening.
The practical implication is that proportionality must be backed by a real service map, not a policy statement. Teams need to know which functions support client activity, settlement, reporting, treasury movement, or other time-sensitive operations, and which supporting systems would trigger outsized loss if unavailable or corrupted. Once that is clear, control depth can be scaled to the importance of the service rather than the number of assets.
This is where a broader governance view helps. DORA alignment should also reflect how resilience and access decisions are prioritised across the environment, so the controls around critical paths remain stronger than controls around low-impact systems. For teams looking to anchor that prioritisation in a formal compliance and audit lens, NHIMG’s Ultimate Guide to NHIs, Regulatory and Audit Perspectives is useful because it ties governance obligations to identity and access review discipline. The regulatory basis for the proportional approach is set out in EU Digital Operational Resilience Act (DORA), which frames resilience around ICT risk, incident handling, and critical third-party dependencies.
How to prioritise controls around critical business services
The best implementation pattern is to begin with a tiered service model. Identify the few services whose disruption would create material customer, financial, regulatory, or market impact, then trace the applications, infrastructure, interfaces, and vendors that support them. Controls such as segmentation, redundancy, monitoring, privileged access restrictions, and recovery testing should be strongest on those paths because those paths define the actual resilience outcome.
That approach avoids a common mistake: spreading effort evenly across every host, account, and application because it feels fair. Equal treatment is rarely proportional treatment. A reporting batch job and a payments gateway do not deserve identical recovery design, alerting depth, or testing frequency. The correct question is whether a failure in that component would interrupt a critical business function or delay an obligation that DORA expects the firm to sustain.
For teams that need a control baseline to translate prioritisation into implementation work, the most useful external references are NIST Cybersecurity Framework 2.0, which organises governance, protection, detection, response, and recovery, and CIS Controls v8, which helps turn criticality into concrete inventory, access, logging, and recovery priorities. For third-party and service-provider exposure, SOC 2 Trust Services Criteria is a practical companion where vendor resilience and operating effectiveness need to be assessed, not assumed.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
NIST CSF 2.0 and CIS Controls v8 set the technical controls, while DORA define the regulatory obligations.
| Framework | Control / Reference | Relevance |
|---|---|---|
| NIST CSF 2.0 | GV — Govern | DORA proportionality needs governance to set service criticality and resilience priorities. |
| ID — Identify | Critical business functions and dependencies must be mapped before control depth is set. | |
| RC — Recover | DORA is fundamentally about keeping essential services operating through disruption. | |
| Recommendation — Set resilience priorities by critical service and governing risk appetite. Inventory critical services, dependencies, and impact paths before tuning controls. Define recovery objectives and test restoration for the most critical services first. | ||
| CIS Controls v8 | 01 — Inventory and Control of Enterprise Assets | Prioritisation depends on knowing which assets support critical services. |
| 05 — Account Management | Stronger access control is needed on the accounts that can affect critical business functions. | |
| 08 — Audit Log Management | Critical services need stronger detection and evidentiary logging for incident response. | |
| Recommendation — Maintain an accurate asset inventory for systems that support critical services. Restrict and review privileged accounts tied to critical business services. Enable and retain logs on the systems that matter most to operational resilience. | ||
| DORA | ICT — ICT Risk Management | The act requires financial entities to manage ICT risk proportionately to business impact. |
| IR — Incident Reporting | Critical services require timely detection and reporting when disruption occurs. | |
| TPRM — ICT Third-Party Risk Management | Key services often depend on vendors, so resilience must extend to third-party dependencies. | |
| Recommendation — Align controls and testing to the ICT services that support essential operations. Prioritise incident handling and reporting for systems supporting critical functions. Assess and contractually control third parties that support critical business services. | ||
Practitioner Guidance
What to prioritise: Build the resilience programme around a small set of critical services first, then expand only where the business impact justifies the extra control depth. If you cannot name the service owner, recovery objective, and key dependencies, you are not ready to tune controls proportionally.
What to verify: Check that segmentation, incident response runbooks, and testing scenarios are aligned to the services that would hurt most if interrupted. The signal of maturity is not broad coverage, it is evidence that the highest-risk paths are tested more rigorously and recovered faster than low-impact assets.
Common mistake: Treating DORA as an enterprise-wide hardening exercise instead of a resilience design problem. That often produces expensive control sprawl while leaving the true critical path under-tested or poorly owned.
Practitioner takeaway: Proportionality works only when the organisation is willing to protect some services more aggressively than others, based on measured business impact rather than technical symmetry.
Related resources from NHI Mgmt Group
- How should financial services teams implement zero trust access without slowing operations?
- How should financial services teams implement generative AI without increasing fraud and deepfake risk?
- How should financial institutions implement PAM to support DORA compliance without creating operational bottlenecks?
- How should financial institutions implement real-time AML alerts without overwhelming compliance teams with false positives?
