Meet the Instructor

Hallie Tremaine Balkin brings over 20 years of experience in federal acquisition, agile contracting, and U.S. defense. She currently serves as General Counsel at Rhombus, where she leads all legal, compliance, and government contracting functions for the company. At Rhombus, Hallie drives strategy at the intersection of law, innovation, and mission delivery—helping accelerate secure, compliant growth in the federal and defense markets.

In addition, Hallie is an Adjunct Professor at The George Washington University Law School, where she developed and teaches the school’s inaugural course on Other Transaction Authority (OTA).

Previously, she was Lead Counsel for Microsoft’s Department of Defense and Defense Industrial Base business, supporting a team that achieved $6.5B in 2024 revenue. Before that, she served as Director for OTA at the Defense Acquisition University (DAU), where she developed the OTA credential. Hallie also provided legal guidance on high-impact efforts such as Operation Warp Speed and the DoD OTA Guidebook.

Earlier in her career, Hallie served as Associate Counsel at Naval Information Warfare Systems Command (NAVWAR), leading acquisition efforts for major projects such as the $2B NOBLE contract and the Navy’s first AI Prize Challenge (AI ATAC).

Hallie earned her Juris Doctor from Thomas Jefferson School of Law and her B.A. in Political Science from San Diego State University.