Dennis M. Horn is a real estate attorney in Holland & Knight's Washington, D.C., office. Mr. Horn's real estate and public law practice spans more than 30 years. He has weathered the real estate cycles by his commitment to anticipating market trends and becoming knowledgeable in specific areas that have helped his clients to be profitable. Mr. Horn's practice emphasizes large private real estate funds, U.S. General Services Administration (GSA) leasing and regulations, public-private partnerships, commercial leasing, and acquisition and development transactions.

Over the course of his career, he has worked on a wide range of matters for clients, including retirement housing, law firm leases, developer/investor joint ventures, student housing, infrastructure development, and real property acquisition and development.

Representative Engagements

  • Representing Amtrak on its $1.1 billion high-speed rail project from Washington, D.C., to New York City
  • Advised clients on the acquisition, development and leasing of various retail and office projects aggregating more than 800,000 square feet in Washington, D.C.
  • Represented several real estate funds in acquiring more than $2 billion in U.S. government and state government-leased real estate assets
  • Represented Children's National Health System in its acquisition and redevelopment of an 8-acre site with six buildings in the former Walter Reed Army Medical Center from the U.S. government
  • Represented Children's National Health System in a "build-to-suit" medical office building lease with outpatient surgical center in Prince George's County, Md.
  • Represented a developer in a public-private partnership with the District of Columbia government to build a 600,000-gross-square-foot (GSF), mixed-use project in the District's West End that includes high-rise residential apartments and condominiums, affordable housing, a public library, a fire station and a squash facility
  • Counseled small businesses in Washington, D.C., on a wide variety of legal issues
  • Advised on a 600,000-GSF, mixed-use project on Capitol Hill that involved a ground lease from the District of Columbia, including retail, rental housing, affordable housing and office space
  • Negotiated multiple joint venture agreements between developers and equity investors
  • Led a task force that advocated for regulatory reform in the District of Columbia


  • University of Pennsylvania Law School, J.D.
  • University of Rochester, B.A., Economics and History, magna cum laude
  • The London School of Economics and Political Science, M.S., Planning Studies in the Faculty of Economics
Bar Admissions/Licenses
  • District of Columbia
  • Florida
  • American Bar Association Real Property, Trusts and Estates Section, Governing Council; Community Outreach Committee, Chair; Future of Law Task Force
  • District of Columbia Bar Association
  • The Florida Bar
  • District of Columbia Building Industry Association, former Board of Directors, former Federal Relations Committee Chair
  • Leadership Greater Washington, Class of 2009
  • Holland & Knight D.C. Political Action Committee Board
  • District of Columbia Chamber of Commerce, former General Counsel; former Executive Board; former Board of Directors; former Education Committee Chair
  • D.C. Education Compact, former Business Representative
  • National Association of Senior Living Industries, former Vice President
  • D.C. Regulatory Reform Project, "Mapping the Steps toward Economic Revitalization," D.C. Project Leader
  • Montgomery County, Md., Friends of the Library, General Counsel
Honors & Awards
  • The Best Lawyers in America guide, Real Estate Law, 2019, 2020
  • Washington, D.C., Super Lawyers magazine, 2007-2019
  • Corporate Counsel Edition, Super Lawyers magazine, May 2009
  • Excellence In Writing Award (Best Overall Article in Probate and Property Magazine), 2007
  • Phi Beta Kappa
  • Martindale-Hubbell AV Preeminent Peer Review Rated


Speaking Engagements