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ISO 27001 Compliance & Audit Readiness

ISO 27001 implementation, Statement of Applicability development, and audit-ready evidence libraries for organizations pursuing information security management certification.

Bell Tower engineers information security management systems aligned to ISO 27001 requirements, with particular focus on Statement of Applicability rationale and Annex A control implementation for regulated organizations.

What We Deliver

  • Statement of Applicability (SoA) Engineering: Inclusion/exclusion decisions with defensible rationale, scope boundaries, and control justification that satisfy certification auditors
  • Annex A Control Mapping: Implementation guidance for all 93 controls across 4 organizational, 7 people, 7 physical, and 34 technical domains
  • Risk Assessment & Treatment: ISO 27001-compliant risk register with treatment plans, residual risk acceptance, and management review documentation
  • Evidence Library: Organized documentation of control operation, testing, and effectiveness for stage 1 and stage 2 audits
  • Certification Audit Preparation: Internal audit execution, management review facilitation, and auditor relationship management

ISO 27001 Implementation

Bell Tower’s ISO 27001 consulting spans the full certification lifecycle. We begin with gap assessment against Annex A controls, identifying which of the 93 controls apply to your organization and which can be excluded with defensible rationale. Our deliverables include the Statement of Applicability with detailed justification for each inclusion, exclusion, and implementation status.

We engineer the ISMS (Information Security Management System) documentation suite: information security policy, risk assessment methodology, risk treatment plan, and procedures for the 14 control categories. Unlike template-heavy approaches, we build controls that map to your actual business processes and risk profile.

For organizations already operating under NIST CSF or CIS Controls, we provide crosswalk documentation showing how existing controls satisfy ISO 27001 Annex A requirements—avoiding redundant implementation while ensuring certification readiness.

Annex A Control Crosswalks

ISO 27001 Annex A controls map directly to common regulatory requirements:

ISO 27001 ControlControl DescriptionHIPAA MappingFINRA/SEC MappingSOC 2 Mapping
A.5.1Information security policies164.308(a)(1)Cyber Rule 2.1CC1.1
A.8.1User endpoint devices164.312(b), (d)Rule 30(a)CC6.1
A.8.9Configuration management164.308(a)(7)Notice 21-29CC7.1
A.8.24Information security testing164.308(a)(8)Rule 2.2CC4.1
A.9.4Access control164.312(a)Cyber Rule 2.2CC6.2
A.12.3Information backup164.308(a)(7)Rule 17a-4(f)A1.2

We map your existing security program to Annex A, identifying gaps and building remediation roadmaps that prioritize high-risk areas first.

Statement of Applicability Examples

The SoA is where most ISO 27001 implementations fail audit. We engineer inclusion/exclusion decisions with rationale that withstands auditor scrutiny:

Example: A.7.13 — Equipment disposal (Excluded)

Rationale: Organization operates cloud-native infrastructure with no on-premise equipment. All hardware managed by AWS/Azure under ISO 27001-certified data centers. Exclusion justified; compensating controls addressed under A.5.23 (cloud service agreements).

Example: A.8.9 — Configuration management (Partially Implemented)

Rationale: Configuration management implemented for production environments (A.8.9 applied). Development environments use infrastructure-as-code with automated compliance checking (A.8.24 applied). Partial implementation justified with plan to extend to non-production by Q3.

Audit Evidence Library

Certification auditors require proof that controls operate effectively. We build evidence libraries organized by Annex A control:

Control RefEvidence TypeSourceOwnerRefresh Cadence
A.5.1Policy versions, approval recordsDocument managementCISOAnnual
A.6.3Training completion reportsLMSHR/SecurityQuarterly
A.8.9Configuration scan reportsCSPM toolsInfrastructureMonthly
A.9.4Access review attestationsIAM systemsData OwnersQuarterly
A.12.3Backup test results, restoration logsBackup systemsOperationsMonthly

From Automation to Auditor

Compliance automation tools (Vanta, Secureframe, Drata) generate evidence, but auditors require context and ownership documentation. We bridge the gap:

  • Evidence Narratives: Convert scan outputs into control operation descriptions auditors understand
  • Sampling Methodology: Document how automated evidence represents the full control population
  • Exception Handling: Clear documentation of control failures, compensating measures, and remediation timelines
  • Management Review: Quarterly ISMS review documentation that shows continuous improvement (required for surveillance audits)

Knowledge Transfer

ISO 27001 certification requires ongoing operation, not just documentation. We ensure your team understands:

  • How to maintain the SoA as organizational scope changes
  • Risk assessment methodology updates when threats evolve
  • Internal audit execution and nonconformity management
  • Management review facilitation and corrective action tracking

Your certification belongs to you. We engineer the system, document the evidence, and ensure your team can operate it independently.


Ready for ISO 27001 certification? Contact us to discuss your current state and certification timeline.