Valiant Integrated Defense Services Announces Appointment of Sean Mattingly as Chief Executive Officer
16 Oct 2025
HERNDON, VA, October 16, 2025 – Valiant proudly announces an important leadership transition that marks the next chapter in our continued growth and success. Effective October 14, 2025, Sean Mattingly has been appointed as Chief Executive Officer (CEO), succeeding Mike Devoto who now assumes the new role of Senior Advisor.
This planned transition reflects the culmination of a thoughtful and deliberate process to position the company for long-term strength, continuity, and innovation. Over the past year and half, Mike Devoto led Valiant through a successful phase of transformation —strengthening our foundation, expanding capabilities, and ensuring the company is well prepared for the future.
We welcome Sean Mattingly as our new CEO and are confident that his leadership will carry forward the values and momentum that define Valiant. Sean brings 35 years of senior leadership experience including 15 years as an executive and 20 years with the United States Marine Corps. Sean’s extensive experience ranges from operations management to strategic growth and customer engagement within the defense and services industry. He has a deep understanding of our mission, our customers, and the standards of excellence that distinguish our organization. Under Sean’s leadership, Valiant’s continued focus is on delivering exceptional performance, operational excellence, and the highest levels of support for our clients and partners.
As Senior Advisor, Mike Devoto remains actively involved in supporting Sean throughout the transition period and beyond, ensuring a seamless handoff and continued alignment with our strategic objectives. We express our sincere appreciation to Mike for his leadership, vision, and dedication in guiding the organization through this important period of progress.
We deeply value the trust and collaboration of our partners and clients. Your continued support has been essential to our success, and we look forward to building on that strong foundation together as we enter this new era of leadership.
About Valiant
Valiant empowers our customers’ most critical missions by training, equipping, protecting, sustaining, and supporting those who serve. Valiant’s 4,500 employees enable government departments and agencies, global peacekeepers, relief workers, and disaster response teams to complete their missions efficiently and effectively in some of the most complex environments worldwide. Valiant deploys expertise for customers in the areas of Training, Simulation, and Readiness; Critical Mission and Language Support; Advanced Logistics & Sustainment; Intelligence & Analysis Solutions; Global Contingency & Stability Operations; and Facility Modernization, Operations, and Maintenance. Valiant is based in Herndon, VA and is a wholly owned subsidiary of GC Valiant LLC. For more information, visit www.onevaliant.com, and follow Valiant on LinkedIn or Facebook.
For media inquiries:
Karen Leonard
Vice President of Proposals and Communications
M: +1 703 851 0008