Don counsels international and domestic entrepreneurs, investors, philanthropists, and privately-held businesses in the tax and legal issues relating to their investments, business activities, estate planning, and charitable endeavors. He has also served as a mediator and an advocate in disputes involving the control of privately-owned businesses, investment ventures, and family trusts.

His writings and speeches have been sponsored by such organizations as the American Bar Association and various state and local bar associations, the International Bureau of Fiscal Documentation, American College of Trusts and Estates Counsel, the Society of Trust and Estate Practitioners, Vanderbilt University, the Institute for International Research, Trusts and Estates, Family Office Exchange, Institute for Private Investors, and the Bureau of National Affairs.

Don served in the Office of the Judge Advocate General of the Navy, was a Partner in Jones Day for twenty years, and later a Partner in Bryan Cave.

Don participates in an interdisciplinary peer group of recognized advisors devoted to a family wealth management practice, known as the Collaboration for Family Flourishing. He is listed in the Best Lawyers in America and Chambers (USA).

He is a participant of “Shaking the Tree: Interactive Productions,” a non-profit production company that uses theater to inspire positive change in family relationships and philanthropic endeavors. Don is also an advisory board member and former director of Learn/Serve International, an international education program for high school students and a director of certain family-funded foundations.

Current Experience

  • Conflict resolution in the context of family offices, family businesses, and private equity, including both advocacy in an arbitration setting and neutral evaluation in mediation.
  • Tax planning and controversy advice, and partnership and governance planning, for family offices, active investors and philanthropists, entrepreneurs and multi-national families.
  • U.S. tax planning and structuring for international investors and immigrating and emigrating clients.

Recent Special Projects

  • Fiduciary review and report to independent board of directors on the suitability of an offshore investment structure intended to change the strategic direction of an operating business (working as a member of an interdisciplinary team).
  • Represented trustees as tax advisor fact witness and expert witness in complex state court litigation in the U.S. concerning proper U.S. tax characterization, remediation, and compliance for trusts created 20 years ago by non-U.S. persons.
  • Developed special ownership structures that allow families to harmonize ownership of a family business with their charitable objectives, even when using U.S. private foundations.
  • Developed intra-family investment methods for use with GRATS while avoiding reliance on expensive financial products.
  • Developed U.S. tax compliant methods for families who seek a voice on public policy issues to fund advocacy, lobbying and electoral activities without being crippled by regulatory roadblocks and excessive disclosure.

Past Experience

  • Developed the legal framework for a “distributed resources” family office structure, which allows each family branch to operate its own distinct customized office while outsourcing defined functions to a central family resources office.
  • Developed a multi-state method for updating trust governance through private trust companies and protector companies, and for reducing state income taxes on trusts.
  • Developed a method for applying the principles of pre-transaction gifting to a grandfathered generation-skipping trust.
  • Created a format and style for estate planning documents to make it easier to describe the client’s plans and intentions, to promote beneficiary education and to minimize tax jargon.
  • Continuation planning for closely held family businesses including governance, estate and tax planning.
  • Tax advice, and legal opinions, for trust departments employing financial products in personal trusts.
  • Tax and partnership advice in structuring and documenting real estate offerings and negotiated joint ventures for national real estate developers, cross border investors, manufacturers, technology companies, trade associations and other non-profits.
  • Tax and general legal advice for start up technology ventures, including licensing, and governance, executive compensation and financing arrangements.
  • Major commercial contract litigation.

Law Reform Experience

  • Past Chair of ACTEC’s Washington Affairs Committee.
  • Participated in the ACTEC comments on the application of the passive loss rules under the US tax code as applied to trusts for business-owning families.
  • Participated in the legislative and regulatory process leading to an exemption from federal investment adviser registration for single family offices.
  • Multiple commentaries on proposed U.S tax rules for attributing taxable powers to U.S. family members who serve in private trust companies.
  • Multiple commentaries on proposed U.S. tax rules for attribution to U.S. beneficiaries of trust-owned shares in foreign companies.
  • Participated in the successful effort to amend the proposed Uniform Trust Code for the District of Columbia, in particular to allow quiet trusts and facilitate trust remodeling.
  • Advice and commentary on amendments to trust laws in various U.S. jurisdictions, including those relating to decanting, trust modifications, private trust company regulation, and directed and quiet trusts.
  • Led an ad hoc group of tax advisors in a successful effort to challenge the attempt by the U.S. Treasury Department to extend the U.S. generation-skipping tax to non-U.S. gift and estate transfers.
  • Participated in efforts to reform the U.S. tax rules for non-U.S. trusts, for S corporations and for deferred payment of estate taxes under IRC section 6166.
  • Commentary on early proposals to eliminate estate and gift tax valuation discounts for family owned businesses.
  • Advice to offshore jurisdictions on corporate and trust statutes intended to facilitate investment by multi-national families in the U.S.

Below are lists of selected Articles and Speaking Engagements.

Professional Licenses
and Designations

  • Attorney (Washington, D.C. and New York)
  • Admitted to Appear Before the U.S. Tax Court

Professional Affiliations

  • Fellow of the American College of Trusts and Estates Counsel (WAC, Charitable and Business Planning Committees)


  • Juris Doctor (J.D.), Harvard Law School (cum laude)
  • Bachelor of Arts (B.A.), Villanova University (cum laude)




  • Best Lawyers® in America Rankings 2024 Edition
  • Chambers and Partners-KHD Attorneys Rank in High Net Worth Guide 2023
  • KHD NY and DC Attorneys Recognized in Best Lawyers in America 2023 Edition
  • Chambers and Partners-KHD Attorneys Rank in High Net Worth Guide 2022
  • Chambers and Partners-KHD Partners Rank in High Net Worth Guide 2021
  • U.S. News and Best Lawyers-KHD Best Trusts and Estates Lawyers 2020
  • Chambers and Partners-KHD Partners Ranked in High Net Worth Guide 2020
  • U.S. News and Best Lawyers-KHD Best Trusts and Estates Lawyers 2019
  • Chambers and Partners-KHD Partners Rank in High Net Worth Guide 2019
  • U.S. News and Best Lawyers-KHD Best Trusts and Estates Lawyers 2018
  • Who’s Who Legal–Leading Private Client Attorneys 2018
  • U.S. New and Best Lawyers-KHD Best Trusts and Estates Lawyers 2017
  • Chambers USA-KHD Partners Leading Individuals in Private Wealth Law 2017
  • Who’s Who Legal–KHD Partners Leading Private Client Attorneys 2017
  • Chambers USA-KHD Leading Law Firm in Private Wealth Law 2016
  • Who’s Who Legal–KHD Partners Leading Private Client Attorneys 2016
  • Chambers USA-KHD Partners Leading Individuals in Wealth Management 2016
  • Chambers USA-KHD DC Partner Leading Individual in Wealth Management 2015
  • ACTEC- Don Kozusko to Head Up Special Project Team 2014
  • ACTEC-Don Kozusko Named to Washington Affairs Committee 2007