About Us

Who We Are


Centurion Group DC, LLC (Centurion) was founded to offer clients a better solution for government relations regulatory compliance management. After spending years honing his expertise in compliance and business management, Centurion founder Patrick Callahan realized there must be a better way to help businesses navigate the niche world of political activities compliance. In 2011, Patrick formed Centurion in order to provide all industries with the kind of broad experience and precise knowledge that a dedicated, outsourced organization can deliver.

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Click here for a one-page information sheet.

Our Mission

Provide adaptive compliance and control risk management solutions that enable clients to focus on business objectives while addressing the challenging climate of global political and government relations compliance. Simply put: we promote a culture of compliance in your business while saving you time and money.

Meet the Leadership Team

Patrick M. Callahan


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Mr. Callahan’s expertise with political activities compliance matters includes, but is not limited to, legislative and procurement lobbying disclosures, pay-to-play, campaign contributions and finance, gift tracking and disclosure, foreign agent registrations, and political action committee and fundraising communications compliance. Mr. Callahan has been described as, “the person you want in a high pressure demanding environment. He is absolutely in charge–nothing gets overlooked and he is anticipating the next ten things before anyone else has thought about them. ” -Serena Moe, Former Managing Director, General Counsel, Global Sanctions Compliance, Citigroup. 

With more than 25 years of professional hands-on business management and compliance experience, Mr. Callahan offers Centurion Group DC, LLC clients the necessary expertise in dealing with regulatory disclosures matters. He also brings to the business an expertise in risk management, operations and project management, continuity planning, information security, financial planning and analysis, governance, event planning, auditing, and policy management. Mr. Callahan is a member of the Society of Corporate Compliance and Ethics.

A native of Florida, where he studied Business Management at Jacksonville University, Callahan currently resides in the Logan Circle neighborhood of Washington, DC where his love of animals includes his feisty Brussel Griffin and a Black Labrador.  He is an active member of Luther Place Memorial Church, and serves on the Church Council Leadership Team.

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Shannon E. Patrick



Shannon Patrick manages the team, focusing on business development, operations, and client relations. An active member of the professional community in Washington, DC, she is the current Co-Founder of GAIN: Government Affairs Industry Network, former Communications Chairperson of the Young Leadership Network, a member of Women in Government Relations, a mentor for the Public Leadership Education Network, a student at the Ethics & Compliance Initiative, and a member of the Society of Corporate Compliance & Ethics. Shannon joins Centurion Group DC with prior experience in government affairs, social media marketing and brand discoverability, research, and writing.

A native of Baltimore, Maryland, Shannon attended the University of Maryland, College Park where she studied English Language & Literature. She lives on Capitol Hill with her boyfriend and dog, and in her spare time enjoys seeing live music with family and friends.

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