Ioannis Koskinas, 

Ioannis "Gianni" Koskinas is a retired special operations military officer, published author, highly effective leader, coach, and mentor. Prior to retirement, Gianni focused on national security matters as senior advisor to General Stan McChrystal (twice), General Nordy Schwartz (Chief of Staff, U.S. Air Force), and the Honorable Mike Vickers (Assistant Secretary of Defense for Special Operations/Low Intensity Conflict).


In commercial life, he has focused on extractive industries, capacity development, aviation, risk mitigation strategies, and bespoke consulting for Fortune 500 company initiatives.

Toby Jackman, 
Director Business Development

Toby joins us from the Private Security Sector where he specialized in delivering solutions for large scale government contracts, particularly for the diplomatic community in high threat, complex environments.


Prior to moving into the Private Security Sector Toby served for 21 years as an infantry officer in The British Army’s Brigade of Gurkhas spending well over half of his military career assigned to overseas postings in Europe, Central and South East Asia. A graduate of the Royal Military Academy Sandhurst, Toby was commended for distinguished services in Afghanistan in 2009 and appointed a Member of the Most Honorable Order of the British Empire (MBE) in 2011.

Costa Maroulis, 
Strategic Advisor

Constantinos (Costa) Maroulis | Director, Business Development, US Government

Costa brings over 20 years expeditionary USG contracting experience to the Hoplite Group Business Development Team. He holds BA degrees in both International Relations and Languages, and served in the US Air Force as an intelligence analyst, operator and linguist in both French and Arabic. After the USAF, Costa was a senior program manager for USCENTCOM Programs for ITT Systems, where he spent almost 10 years living in KSA and later Qatar. More recently, he has concentrated his efforts as a solution architect for expeditionary contracting for both DoD and DoS.

Rachel Halvorson, 
Director of Administration

Rachel is a 2006 graduate of Auburn University and received her commission through Air Force ROTC. She moved to the private sector after serving as a maintenance officer in Air Force Special Operations Command at Hurlburt Field, Cannon AFB and Bagram AB, Afghanistan primarily working AC-130H gunships.


Rachel is currently working as our Director of Administration & Finance. She handles all administrative matters to include finance, human resources and day to day business operations. She also assists with drafting policies, ensuring business compliance and serves as our Facility Security Officer.


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Hoplite Group

Veteran Owned Small Business

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