Mid–Senior Proposal Manager, Hybrid-eligible; GT

About GTSC

GTSC is a fast-growing federal IT services contractor supporting civilian and DoD customers across IT modernization, cybersecurity, data, systems engineering, and mission support. We are investing deliberately in our growth organization to improve proposal quality, execution rhythm, and win consistency across complex, high-value pursuits.

Chantilly, Virginia, Hybrid-eligible

GTSC is seeking a Mid–Senior Proposal Manager to lead large, complex federal proposals in the $35M–$50M range across a mixed civilian and defense portfolio. This role owns proposal execution end-to-end and plays a key role in improving proposal discipline, predictability, and quality as GTSC scales.

You will work closely with Capture Managers, technical leaders, partners, and executives to deliver compliant, compelling proposals-while helping standardize and continuously improve GTSC's proposal processes.

• Lead and manage multiple federal proposal efforts from kickoff through submission
• Develop proposal schedules, outlines, compliance matrices, and writing assignments
• Drive proposal cadence, daily standups, and internal reviews
• Ensure full compliance with RFP requirements and evaluation criteria
• Coordinate writers, SMEs, partners, and subcontractors across the proposal lifecycle
• Author or refine proposal sections (e.g., management approach, executive summaries) as needed
• Leverage AI/LLM tools to improve drafting efficiency, content quality, and compliance checks
• Improve proposal rhythm, reduce fire drills, and raise overall submission quality
• Capture lessons learned and contribute to reusable proposal content and standards

• Successfully leads multiple major proposals through submission
• Improves proposal execution rhythm and predictability
• Raises quality, compliance, and evaluator readability
• Reduces last-minute churn and unmanaged risk
• Becomes a trusted execution partner to Capture and Growth leadership

• Bachelor's degree or equivalent experience
• 5+ years of federal proposal management or closely related experience
• Experience leading large, complex proposals ($35M+)
• Strong understanding of federal RFP structures and compliance
• Ability to manage cross-functional teams under deadline
• Proficiency with Microsoft 365 and collaborative proposal environments
• Comfort using AI/LLM tools to support proposal development

• Experience supporting both Fed Civ and DoD customers
• Familiarity with Shipley or similar proposal methodologies
• Experience with IDIQs, GWACs, and task-order-based proposals

GTSC is proud to be an equal opportunity employer, committed to recruiting, hiring, and promoting qualified people of all backgrounds, regardless of sex; race; color; creed; national origin; religion; age; marital status; pregnancy; physical, mental or sensory disability; sexual orientation; gender identity or any other basis protected by federal, state or local law. Learn more about your EEO rights as an applicant.

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GTSC participates in the E-Verify program in certain locations as required by law. Learn more about the E-Verify program.

Employment in this position is contingent upon the successful completion of a background check. Depending on the nature of the job duties or requirements set forth by our government clients, additional screenings such as drug testing and/or credit checks may be required. These checks are conducted in accordance with all applicable federal, state, and local laws.