Matthew Mosellen

Matthew Mosellen serves as a Contracting Officer within the Contract Administration Services Division (70RCAS) of the Department of Homeland Security’s Office of Procurement Operations, where he plays a pivotal role in executing mission-critical acquisitions that support national security and operational readiness. He manages the full lifecycle of professional, scientific, and technical service contracts, with a primary focus on custom computer programming, systems engineering, and cybersecurity solutions. His work ensures the integrity and modernization of DHS’s technical infrastructure by aligning procurement outcomes with strategic R&D priorities and compliance requirements under the Federal Acquisition Regulation. Mosellen maintains collaborative relationships with a diverse pool of vendors, including large prime contractors specializing in defense and federal IT services, as well as niche technical firms with deep expertise in software development and systems integration. He fosters transparent, performance-based contracting environments that emphasize deliverables, technical compliance, and contractor accountability. His approach prioritizes long-term vendor partnerships grounded in past performance, quality assurance, and adherence to cybersecurity standards such as NIST SP 800-53 and CMMC frameworks. His contracting portfolio reflects a strong emphasis on socioeconomic inclusion, with 20% of his awards designated as Total Small Business Set-Asides under FAR 19.5, demonstrating a deliberate commitment to expanding opportunities for small businesses. While the majority of his acquisitions are unrestricted, he actively promotes small business participation through targeted outreach and structured competition, ensuring alignment with DHS’s broader goals for equitable contracting. Mosellen’s primary procurement focus lies in NAICS 541511 (Custom Computer Programming Services), where he acquires bespoke software development, legacy system modernization, and mission-critical application support. He also regularly procures services under NAICS 813920 (Professional Organizations), engaging trade associations and technical consortia to leverage industry expertise in standards development and workforce training. His domain expertise centers on cybersecurity infrastructure, systems engineering, and applied research in physical and engineering sciences.