Grant Willis's practice focuses on litigation, investigations, and counseling related to government procurement. He has advised U.S. and international firms in the defense, construction, energy, aerospace, information technology, and engineering contracting industries in matters including contract/subcontract negotiations, bid protests, CDA claims, subcontractor disputes, DCAA audits, debarment proceedings, internal investigations, contract novations, and corporate mergers, acquisitions, and reorganizations. Grant has advised and represented clients in connection with allegations and issues regarding the False Claims Act, the Anti-Kickback Act, the Procurement Integrity Act, the Truth in Negotiations Act, cost allowability and the Cost Accounting Standards, patent and data rights, GSA schedules, organizational conflicts of interest, government indemnification, security clearances, SBIR participation and other small business matters, affirmative action requirements, small business subcontracting plans, domestic preference laws, Title III of the Defense Production Act, and FTA-funded procurements.

Grant's pro bono activities include counseling local nonprofit entities and representing local needy families, disabled U.S. veterans, and asylum applicants. His experience extends to matters in front of the U.S. Court of Federal Claims, the Civilian and Armed Forces Boards of Contract Appeals, the GAO, the District of Columbia Contract Appeals Board, the World Bank Sanctions Board, as well as various U.S. district courts, U.S. courts of appeal, federal administrative bodies, and state courts.