Adversary-informed cybersecurity consulting

A security program is only as strong as the decisions behind it.

OP4 is a cybersecurity consulting firm. We help organizations identify gaps, mature their security programs, and make better security decisions — practical guidance aligned to the business.

Start a conversationExplore services
01Services

Senior security leadership, scaled to your size.

Consulting-led and adversary-informed. Most engagements start with a focused assessment or a fractional-leadership retainer, then grow into whatever the program needs.

Flagship — ongoing partnership
FlagshipRetainer

Fractional CISO (vCISO)

Senior security leadership without a senior-leadership hire — the strategy, roadmap, and oversight of a CISO at a fraction of the cost.

Who it's for — mid-sized organizations with thin or dual-hatted IT and no full-time CISO.
Includes — program strategy, roadmap ownership, risk decisions, vendor & board reporting, and a steady hand on priorities.
Discuss a retainer →
Wedge → annuity

Compliance readiness & monitoring

Customers or insurers requiring proof of security? We get you ready for SOC 2, ISO 27001, HIPAA, CMMC, or cyber-insurance — then keep you there with continuous monitoring.

Readiness — gap analysis, control build-out, and evidence prep ahead of the audit.
Monitoring — ongoing control upkeep so you stay compliant between cycles.
OP4 delivers readiness and advisory up to the audit — the formal attestation is performed by an independent licensed auditor, not OP4.
Supporting capability
Assessments & testing

Find the gaps before an adversary does.

Penetration testing
Simulate a real attack to prove what's actually exploitable.
Vulnerability assessments
Find and rank weaknesses into a prioritized fix list, not noise.
Risk assessments
Understand which risks actually threaten the business.
Threat modeling
Map how a system could be attacked, at design time.
Application security assessments
Evaluate how your apps are built and where they're exposed.
Tabletop exercises
Half-day facilitated incident simulations for the leadership team.
Strategy, GRC & program

Direction, structure, and a plan to mature.

Security strategy consulting
A clear, prioritized plan for where the program should go.
Program transformation & roadmapping
Turn scattered controls into a sequenced, fundable build.
GRC consulting
Governance, risk, and compliance practices that hold up.
Security policy development
Write policies people can actually follow.
Security awareness training
Practical training that changes how people handle risk.
Productized engagements — fixed scope, fast start
Cyber-insurance readiness
Meet the MFA, EDR, backup, and IR-plan bar insurers now require.
Security health-check
A templated, fixed-price read on where your posture stands today.
Vendor / third-party risk
Vet the security of the vendors your business depends on.
M&A security due diligence
Assess a target's security posture before an acquisition closes.
Also available — beyond core cybersecurity
Security & IT audits
An IT-focused review of controls, configuration, and operational gaps — the complement to the security work above.
AI implementation consulting for SMBs
Practical, secure adoption of AI tools — where it helps, where it doesn't, and how to do it safely.
02About

Built on opposing-force thinking.

In military training, the OPFOR — Opposing Force — is the team that plays the adversary, probing defenses so the real force is ready before it matters. OP4 is built on the same idea: the most useful security advice comes from thinking like the opposition — not to put on a show, but to find the gaps that matter and close them before someone else finds them first.

OP4 LLC is a Virginia-based cybersecurity consulting firm working with small and mid-sized organizations — especially those without dedicated security leadership. The work is the program: practical, business-aligned guidance, with testing as one tool among many rather than the headline.

Andrew Robb
Founder & CEO · 17+ years in information security

Andrew founded OP4 to bring senior, practical security guidance to the organizations that need it most but can't justify a full-time security team. Over 17+ years he has led enterprise vulnerability management programs at scale — overseeing the remediation of millions of vulnerabilities across roughly 100,000 assets — run penetration testing and threat-emulation teams, and advised on security strategy, governance, risk, and compliance across federal, defense, and Fortune-scale enterprise environments.

Security+Core ImpactMetasploit ProQualys VMDRB.A., Virginia Tech
01
Adversary-informed, not adversarial
We study how your environment would be attacked, then turn that into calm, prioritized decisions — no theatrics.
02
Experience over checklists
Recommendations come from years of hands-on work maturing real programs — not a generic framework dump.
03
Built for the business
Every call is weighed against your priorities, resources, and risk tolerance — and explained in plain terms.
Track record
Baker Hughes · 2021–2024
Sr. Manager, Enterprise Vulnerability Management
Transformed VM at a Fortune 200 from reactive and spreadsheet-based into an integrated, metrics-driven program across ~100,000 assets — with modern reporting, CMDB feedback loops, and a vulnerability disclosure program.
CGI · 2018–2021
Penetration Testing Team Lead
Led the US penetration testing and threat-emulation team — hands-on network, application, and wireless testing, secure-SDLC/DevSecOps enablement, and PCI-DSS & HITRUST audit support.
Federal / Defense / IC
Earlier career
GRC consulting and security roles across federal, defense, and intelligence-community environments — the foundation of OP4's adversary-informed, compliance-fluent approach.
03Contact

Tell us where your security stands today.

We'll point you at the most useful next step — whether or not it's with OP4.

Prefer email? andrew@op4.co