In 2025 we set out to celebrate our 95th anniversary. We took time to reflect on the people, projects, and moments that shaped who we are today. We also marked the occasion by creating a company timeline. The challenge wasn’t simply to record dates — it was to translate nearly a century of purpose, innovation, and community impact into something that resonates. We wanted to do more than list events or projects, we wanted to reflect the values and momentum that shaped the firm. While a single timeline certainly cannot capture nearly a century of work, a few milestones offer a look into the moments highlighted in our 95-year timeline.
Founded in Sioux Falls by Harold Spitznagel on June 9, 1930, the firm was built on a commitment to understand clients and their needs. From the start, that philosophy helped to establish a reputation for relationships, high-quality design, innovation, and flexibility.
Along the way, we’ve marked milestones that didn’t just grow the firm, but expanded our ability to make places that matter:
- The design of Sioux Falls City Hall in 1932, Spitznagel’s first major commission, set the stage for decades of civic impact. As the firm grew, so did its capabilities, with full-time engineers and interior designers joining the practice in the early 1950s. By the late 1950s and early ‘60s, landmark projects like the Sioux Falls Arena further solidified the firm’s regional presence.
- Expansion continued in the decades that followed, with new offices opening in Rochester, MN in 1969 and in Rapid City, SD in 1973. That same era brought the arrival of Ron Mielke, who joined the firm in 1969 and remains with TSP today.
- More recently, TSP has continued to invest in the next generation, as we helped start the architecture department at South Dakota State University in 2010.
- And in 2022, the firm became a 100-percent Employee Stock Ownership Program (ESOP) firm, paving the way for our legacy to continue for another century.
These highlights are only a small part of the journey. To explore the nine-plus decades, please visit our 95-year timeline.
Beyond the timeline: additional moments that shaped our firm
Core Values established early
As we dig through the archives, it’s clear our core values have been guiding us from the beginning. “We Before Me, Design It Like We Own It, and Committed To Our Craft” show up early and often in our history, laying the foundation for how we live our role as trusted advisors every day.
A commitment to art and design
When possible, Spitznagel recommended that 1% of a project budget be allocated for interior or exterior art when it enhanced the design. Reflecting his belief in the value of art, the Augustana University art department presents its highest award, the Harold Spitznagel Medal for Achievement in Art, to artists who demonstrate the highest standards of excellence during their careers at Augustana. The award was first presented in 1959.
Service across communities and market sectors
Over the years, TSP has developed a reputation for expertise across a wide variety of project types, from education and healthcare to community projects ranging from churches and libraries to fire stations and retail spaces. Together, these projects reflect the breadth of our work and the communities we’ve served through listening, accountability, and long-term relationships.
A culture that values balance
Fun in the workplace and taking the time to enjoy life have always been part of the TSP culture. As Spitz once said, “We have always operated on more or less a dolce vita (the sweet life) principle, not as far as the client is concerned, but as far as the principals and our employees are concerned. I am sure that we could improve our efficiency immeasurably and it would result in greater profit. But I believe that there are other things in life that are equally rewarding, for instance such a simple thing as taking time to enjoy life.”
Relationships are at the core
It has been noted that our founder “…had an amazing facility for becoming his clients’ respected friend as well as their architect.” We are still driven by this philosophy today.
We also have information on when the first mimeograph was purchased, the year, make, and model of the first company car, office traditions that are strangely similar to today, and hourly wages through the years. But that information is better used at internal trivia contests. Here’s to a long and steady future!
Want to learn more about how Team TSP can help with your next project, give us a call.
