It is with great sorrow that we announce the death of retired Hale and Dorr Managing Partner John D. Hamilton Jr., who passed away on March 3 at the age of 85.

John Hamilton rose to prominence first as a real estate lawyer who helped shape the Boston skyline of the 1970s and 80s and then as managing partner of the law firm Hale and Dorr LLP (now WilmerHale), a position he held for more than 15 years.

Ahead of his time on matters ranging from diversity to public service to technology and large firm administration, Mr. Hamilton is best remembered by family, friends, colleagues and the communities he served as modest, selfless and genuinely interested in the well-being of all those who crossed his path. Wherever he saw a need, an inequity or a better way forward, he was tireless in his determination to effect change. He was, above all, a person of great integrity and decency.

Upon his graduation from Harvard Law School in 1960—following two years’ service in the Navy Reserve Officer Training Corps and the United States Navy Reserve—Mr. Hamilton was recruited to the real estate department of Boston’s Hale and Dorr.

There, he helped reshape the Boston real estate landscape during the city’s revival, becoming an expert in the Boston Redevelopment Authority’s plans for urban renewal. He provided guidance on complex permitting, financing, leasing, construction and maintenance matters, helping his clients translate their vision for Boston’s revitalization into a reality through the development of high-rise office buildings, hotels, factories, apartment complexes and shopping centers. Among many other highlights, he served as counsel to Carpenter & Company in its development of the Charles Hotel in Cambridge and Four Seasons properties across the country. Rising to the position of real estate department chair, he grew the group to what was, by the mid-1980s, the fourth-largest real estate practice in the United States.

In the late 1970s, Mr. Hamilton also took on the role of hiring partner, and brought to Hale and Dorr a collection of exceptional young lawyers that would propel the firm to the forefront of an evolving legal industry. In 1976, he hired William F. Lee, spotting the qualities that would make Lee one of the nation’s foremost trial, appellate and intellectual property litigators, and later the first Asian-American managing partner of an AmLaw 100 firm. In the mid-1980s, he brought in MIT-trained mechanical engineer and Harvard Law School–pedigreed lawyer James B. Lampert to found one of the first intellectual property practices at a general practice law firm. These hires, and many others, helped place Hale and Dorr at the leading edge of the profession as it moved toward the 21st century.

In 1984, the partners of Hale and Dorr asked Mr. Hamilton to become managing partner, making him Hale and Dorr’s fourth leader in its then 66-year history.

As managing partner, Mr. Hamilton was—in the words of Lee, who became his successor in 2000—the firm’s “visionary, architect, builder, mentor and leader.” He transformed Hale and Dorr’s compensation system and governance structure, brought in the firm’s first executive director to build an efficient, strong and effective professional staff, and shepherded the firm’s first steps into the international arena. By 2000, when Mr. Hamilton stepped down as managing partner, the firm had almost doubled its lawyer headcount and added offices in New York City and Reston, Virginia, as well as joint venture offices in London and Oxford, and even a presence in Prague.

Mr. Hamilton was famous for what former colleague Bill O’Reilly describes as his “management by walking around” style, which made him a constant, and genial, presence in the halls. “John was a people person,” says Dan Halston, current partner-in-charge of WilmerHale’s Boston office. “He knew everyone, both lawyers and staff, and would always remember the names of their children and grandchildren.”

Showing remarkable prescience in recognizing the importance of well-being and work-life balance for those in the legal profession, Mr. Hamilton brought yoga and mindfulness programs to the firm. He was also ahead of his time in promoting diversity in law and business, using his position as founding member of the Boston Lawyers Group to encourage the business community to recruit, advance and retain lawyers of color.

Perhaps his greatest professional legacy, however, is the foundation laid by his leadership in pro bono and community service. Marrying his business acumen with his drive to give back to the community, Mr. Hamilton sought out opportunities to make the greatest impact.

After involving the firm as a charter signatory in the Pro Bono Institute’s Pro Bono Challenge, he worked with John F. “Jack” Cogan Jr.—his predecessor as managing partner—to establish the Hale and Dorr Legal Services Center of Harvard Law School (LSC).He and Cogan coordinated a substantial gift from the Hale and Dorr partners, enabling the purchase and rehabilitation of a building to house the LSC in the Boston neighborhood of Jamaica Plain, where the firm’s lawyers became volunteer advocates for Boston’s most underserved communities. Mr. Hamilton and Mr. Cogan were recognized by the LSC with its Bellow-Charn Champion of Justice Legacy Award in 2019, in honor of the 25th anniversary of the organization’s founding.

Upon the launch of the Walden Woods Project in 1990, Mr. Hamilton worked with the organization and its founder, musician Don Henley, to preserve Henry David Thoreau’s iconic Walden Woods. Mr. Hamilton also founded the Hale and Dorr Youth and Education Initiative, employing a pioneering philanthropic model combining financial support, pro bono representation and volunteer service to make a decisive impact on the futures of children and teens. After more than 20 years, the initiative continues to grow.

Mr. Hamilton’s many honors include the Pro Bono Institute’s Chesterfield Smith Award, which recognizes law firm leaders who have demonstrated an extraordinary commitment to equal justice; City Year’s Civic Innovation Award; the Princeton Class of 1955 Distinguished Achievement Award; and WilmerHale’s James D. St. Clair Award for Professional Excellence.