CI-Discern home
Management consulting for critical infrastructure

Discern what is true.
Decide what to trust.

CI-Discern is a management consultancy focused on critical infrastructure with a heritage in cybersecurity. We advise and assist the owners, operators, and overseers who enable and protect the people, assets, and systems that power everyday life.

Discuss your environment Explore our key services
Government Critical manufacturing Water treatment plant Container port

Who We Are

About CI-Discern

CI-Discern was founded to help improve critical infrastructure security and resilience. CI stands for Critical Infrastructure and Discern is a word that channels wisdom to action.

We help your organization (its people, networks, and systems) discern what is true, so you can decide who and what to trust with greater confidence.

CI-Discern is a diverse team of exceptional professionals who believe in and are committed to the shared mission of improving critical infrastructure security and resilience.

Our cybersecurity risk management and compliance services span the critical infrastructure sectors of energy, government, transportation, water and wastewater, and critical manufacturing.

From the boardroom to the control room, we help client teams to improve their cybersecurity and resilience posture by helping to refresh security strategies, design secure, resilient IT and OT architectures, and enable visibility that inspires confidence that controls are working as intended. In addition to improving security, we assist organizations to meet key compliance obligations including NERC CIP, NERC 693, TSA, AWIA, FISMA, NIST CSF, and CMMC with confidence.

Leadership

Experienced security leadership that includes former energy sector and government CISOs and Big 4 consulting executives.

Dillon Dieffenbach
Dillon Dieffenbach
CEO, co-founder
Former EY Partner and Cyber-in-Energy Lead for the Americas with over 25 years of experience.
Greg Sisson
Greg Sisson
COO, co-founder
Former CISO of the U.S. Department of Energy and U.S. Army veteran with over 30 years of experience.
Jim Ball
Jim Ball
CTO, co-founder
Former CISO of the Western Area Power Administration and U.S. Navy veteran with over 40 years of experience.
Steve Swick
Steve Swick
Managing Director, Energy Practice Lead
Former CSO of American Electric Power and U.S. Air Force veteran with over 35 years of experience.

Why CI-Discern

Why clients choose us

1We bring experience, not theory.
Our leaders have served as energy sector and government CISOs and Big 4 consulting executives. We advise from experience in the roles our clients hold today.
2We focus on consequences and outcomes.
High-consequence risks shape our approach. We protect critical systems and enable recovery so organizations withstand disruption.
3We connect operations, security, and leadership.
We bring engineers, operators, security teams, and executives to the same table, so recommendations fit how systems run and are funded and governed.

Our values

Unapologetically people focused

Solutions built around how people actually work and communities thrive.

Partners who stand with you

Shared responsibility, well beyond the contract.

We build continuity

Built to keep essential services running.

Trust earned daily

Transparent, consistent, accountable, every time.

Dillon Dieffenbach
Resilience is built through clarity, discipline, and trust. Our job is to help organizations strengthen all three before disruption occurs. We have the experience, relationships, and technical acumen to help you secure what matters most.
Dillon DieffenbachChief Executive Officer

Client results
Energy
CISO Advisory & Amplification

Top 5 Investor-Owned Utility

Published Cybersecurity Strategy and Secure OT Defense Framework, each tied to operational performance metrics leadership can track.

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Government
IT/OT Strategy, Architecture & Design

U.S. Government Agency

Developed defensible guidance for protecting critical national assets, pairing the zero trust architecture with the program office to deliver it.

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Transportation
C-Suite, Board & Government Advisory

Regional Seaport

One of two firms selected to assist the U.S. Coast Guard in leading a cybersecurity incident response tabletop exercise.

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Government
Assessments & Audit Readiness

Multiple Defense Clients

Delivered audit-ready, sustainable compliance outcomes for organizations serving the Department of War.

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Connect With Us

Whether you want to discuss our sectors, our services, or your own environment, select “Contact us” to speak with an expert.

Contact us [email protected]