As Mairs & Power nears the century mark as an investment advisory firm, Rob Mairs, a third-generation member of the Mairs family, became its chief executive Tuesday.

Mairs, who joined the firm in 2015 as general counsel, succeeds Mark Henneman, a non-family member, in leading the company that was founded by George Mairs Jr. in 1931.

Rob Mairs was selected for the CEO position by the board of directors. Henneman will remain as chairman through the end of 2026. This leadership transition timetable has been in place for years. In a mid-2022 interview, Henneman told Twin Cities Business that he planned to retire from the firm in 2026.

“Succession planning is an integral component of Mairs & Power’s long-term focus,” Henneman said in a prepared statement Tuesday. “The board of directors and I are excited to hand the reins to Rob, knowing that he has been an important part of our growth over the last 10 years. He understands what it takes to ensure the future success of Mairs & Power.”

Rob Mairs had a legal career before he became a part of Mairs & Power, which is owned by employees. For 16 years, he was a lawyer with Minneapolis-based Gray Plant Mooty. Mairs was a partner in the trust, estates, and charitable planning group. In 2020, Gray Plant Mooty merged into the Lathrop Gage firm, which today is known as Lathrop GPM.

After entering Mairs & Power in a general counsel role, within two years Mairs became chief compliance officer. He assumed the No. 2 role as president in 2018. He’s a graduate of three private schools—Saint Paul Academy, Dartmouth College, and William Mitchell College of Law, now Mitchell Hamline School of Law in St. Paul.

In Tuesday’s news release, Mairs praised Henneman for the strong growth he achieved at the firm. Henneman has been with Mairs & Power for 20 years. During that period, he was co-manager and lead manager of the Mairs & Power Growth Fund, president, chief investment officer, CEO, and chairman. Since Henneman’s arrival, firm assets grew from $2 billion to almost $12 billion.

Henneman oversaw the launch of the firm’s first exchange traded fund, Mairs & Power Municipal Bond ETF, led a strategic move into private equity through Mairs & Power Venture Capital, and he increased services for the firm’s advisory clients.

“Mark has had a tremendous impact on making Mairs & Power what it is today,” Mairs said in the news release. “He had the foresight to navigate and embrace change, while bolstering our long-term investment strategy, always striving to provide the highest quality investment products and services for our clients.”

Mairs & Power long has been involved in the civic and commercial life of St. Paul. Henneman currently serves on the boards of the Saint Paul & Minnesota Foundation and the Saint Paul Downtown Alliance.

Henneman, Mairs, and other firm leaders chose to make a continuing commitment to St. Paul in 2022. They had decided to leave the First National Bank Building, where the firm had been located in downtown St. Paul since the 1940s. They could have relocated outside of St. Paul, but opted to invest in a new office on the 25th floor of Wells Fargo Place at 30 East 7th Street.

Mairs & Power, known for taking a disciplined, long-term approach to investing, employs about 50 people.

Mairs & Power draws its name from founder Mairs Jr. and George C. Power Jr., who joined the firm after World War II and built a large base of individual investor accounts. In the mid-1950s, Mairs Jr. offered Power a partnership and renamed his firm Mairs & Power. Those two men and George Mairs III, an uncle to Rob Mairs, shaped and built the firm’s business and culture over many decades.