About Sentinel Risk Group
Experience tested where the cost of being wrong is real.
Sentinel Risk Group is an independent operational resilience and decision-support advisory firm, led by professionals who have made high-consequence decisions in the field and inside complex enterprises. This is who leads the firm — and the standard every engagement is held to.
Firm identity & purpose
Veteran-led is the proof. Disciplined judgment is the product.
Sentinel Risk Group was built by operators — but veteran ownership is supporting proof, not the complete value proposition. SRG’s authority comes from a repeatable standard applied to complex problems, carried by people who have operated where consequence is real.
- Disciplined methodology
- Operator judgment
- Evidence traceability
- Scoring architecture
- Special Operations leadership
- Enterprise operating experience
- Technology, cybersecurity, logistics & compliance expertise
- Sustained support through execution
We do not disguise the problem. We identify it, measure its operational impact, and direct action against it.
We don’t minimize risk with better words. We reduce risk through better decisions.
Combined leadership
More than 50 years of combined Special Operations, operational leadership, and enterprise experience.
Sentinel Risk Group is led by professionals with deep experience across U.S. Army Special Forces and Special Operations, Advanced Special Operations Techniques, complex operational planning, executive decision-making, cybersecurity, logistics, compliance, organizational readiness, and enterprise risk.
That combination matters. SRG applies the disciplined judgment forged in high-consequence environments to the practical realities of technology, accountability, continuity, and operational performance inside complex organizations.
The result is a clearer understanding of what can fail, how those failures connect, what matters most, and what leadership must do next.
Leadership
Mark L. Apperson
Founder & Chief Executive Officer
U.S. Army Special Forces Senior Leader · Green Beret
Mark L. Apperson is the Founder and CEO of Sentinel Risk Group and a senior leader in U.S. Army Special Forces. A Green Beret, he has spent his career planning and leading complex operations in environments where incomplete information and real consequence are the standard, not the exception.
His experience spans complex operations, program and resource management, operational planning, and executive decision support. His background also includes Advanced Special Operations Techniques, intelligence operations, Special Operations Special Access Programs and resource management, senior instructor leadership, and the development of teams operating in sensitive, high-consequence environments — translating ambiguous, high-pressure situations into clear decisions and accountable action. He has led organizations through demanding readiness requirements and risk assessments where the measure of success was not a good briefing, but a defensible decision.
At Sentinel Risk Group, Mark applies that same discipline to the operational realities facing executives and organizations: understanding what can fail, how failures connect, what matters most, and what leadership must do next.
Currently serving in U.S. Army Special Forces and transitioning to civilian leadership.
Leadership
Jeff M. Adamec
Business Operations Manager
Technology, Cybersecurity, Logistics & Compliance
Jeff M. Adamec brings more than 30 years of leadership and operational experience spanning U.S. Army Special Forces, information technology, cybersecurity, logistics, compliance, asset accountability, and organizational risk.
A retired U.S. Army Special Operations and Special Forces Soldier and combat-wounded veteran, Jeff served in the 75th Ranger Regiment and later as a Green Beret and senior noncommissioned officer in complex, high-risk environments across multiple theaters. His military service shaped a disciplined approach to operational planning, accountability, logistics coordination, risk management, and leadership under pressure.
At Sentinel Risk Group, Jeff leads business operations and supports the integration of technology, cybersecurity, logistics, asset accountability, and compliance across the firm’s advisory capabilities. His work strengthens the systems, controls, and operating discipline required to support organizational resilience, business continuity, and effective decision-making.
Jeff also brings extensive corporate experience leading global inventory, compliance, technology, and operational programs within Fortune 100 organizations. He has developed scalable processes, managed cross-functional teams, strengthened audit readiness, and improved operational control across complex enterprise environments.
His expertise connects strategy to execution. Jeff helps organizations identify vulnerabilities, strengthen accountability, improve operational controls, and build systems capable of performing under pressure.
Credentials as proof
The experience behind the methodology.
SRG’s recommendations are backed by proven experience across the domains where operational failure actually happens — presented as evidence of capability, not credentials for their own sake.
Special Operations leadership
U.S. Army Special Forces and Special Operations planning, command, and execution in high-consequence environments.
Operational planning & decision support
Turning incomplete information and competing priorities into clear, defensible executive decisions.
Technology & cybersecurity
Information technology and cybersecurity operations that protect continuity and accountability.
Logistics & supply chain
Logistics, asset management, and supply-chain leadership across complex operations.
Compliance, audit & governance
Compliance, audit readiness, and governance that hold systems to a defensible standard.
Enterprise & Fortune 100 operations
Global inventory, compliance, technology, and operational programs inside Fortune 100 organizations.
Organizational readiness & risk
Readiness, operational risk, and resilience assessment across complex enterprise environments.
Sustained support through execution
Engagement that continues through execution — not a document left behind.
Start with how we think
Understand the standard. Then start the conversation.
See the doctrine that governs every engagement, the methodology it drives, or bring us your environment.