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Winthrop & Weinstine, P.A.

Laura Brown//June 8, 2026//

MN In the Lead Women Led Law Firms logo

Winthrop & Weinstine, P.A.

Laura Brown//June 8, 2026//

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Tammera Diehm, Winthrop & Weinstine
Tammera Diehm

Winthrop and Weinstine is a full-service commercial law firm whose lawyers provide forward-thinking legal representation across a wide range of industries and practice areas. These include corporate transactions, banking and finance, energy, health care, employment, intellectual property, real estate, regulatory matters, litigation, tax, and trusts and estates. 

Tammera Diehm serves as the first female president of Winthrop & Weinstine. As someone who went through law school as a single mother with three young children — and still managed to graduate summa cum laude — she understands the balancing act needed to satisfy clients while managing the firm.

In her role as practicing attorney, Diehm works in real estate transactions, with a particular focus in multi-unit real estate. Diehm has spent much of her time mentoring, leading, and counseling various community programs and activities, including leading the firm to participate in Cristo Rey Network’s Corporate Work Study program.

“We are committed to building a diverse workforce of talented individuals who embody our mission to bring smart perspectives and practical outcomes to the law,” the firm states on its website. “At our core, we believe diversity and inclusion are table stakes and work each day to promote these values through a variety of initiatives, activities and organizations.”

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