This month, Mark Walker is celebrating his company's one year anniversary of going public — only the ninth Black-founded business to accomplish this feat on a U.S. stock exchange. Photo courtesy

After working in both sides of the advertising world, Mark Walker thought he could reimagine a platform that would be more efficient and equitable.

Walker co-founded his company, Direct Digital Holdings, an adtech platform, after serving in several roles — from an early hire at Houston digital media startup Questia to business development director at NRG Energy and COO of EBONY Media. He shares on the Houston Innovators Platform how he took this experience in tech, advertising, and media to create his company's platform.

"NRG Energy gave me a top-down view of the value chain, and Ebony gave me a bottoms-up view of the value chain of how media is purchased," Walker says on the show. "At Direct Digital Holdings, we help companies buy and sell media — and we leverage technology to do it. It's really the culmination of both of those experiences."

With over 30,000 publishers on its platform, Direct Digital makes it easier for its core customers — middle market companies looking to buy into the digital media ecosystem — to tap into these opportunities without the tech know-how they might otherwise need. Walker explains that at EBONY, he saw how small to midsize publications — especially the multicultural ones — were being left out on the ad selling side of the equation. The Direct Digital platform bridges the gap on each end.

Founded in 2018 in partnership with Keith Smith, who went through similar professional experiences, Direct Digital went public exactly one year ago after growing the company through strategic M&A activity. Walker says the decision to IPO made the most sense for his company — though it wasn't an easy process. Direct Digital is only the ninth company founded by a Black entrepreneur to go public on a US stock exchange.

"If you think the process is hard — it actually is," Walker says on the journey to IPO. "We were a privately held company, and we knew we had a good growth trajectory and we looked a couple different options. We decided to go public in a very traditional way."

Walker explains there were some risks involved, but the co-founders ultimately decided to shy away from adding in investors who might not have the same ideas for the company's future.

Direct Digital has been a Houston company from the star — despite the city not being home to a booming adtech ecosystem. Instead, Houston — with its collection of Fortune 500 companies and rich diversity — has allowed the business to stand out.

"If you look at and reflect on how our company has been built — from our board of directors to our leadership and management team — we're a majority minority organization all the way across the board," Walker says. "Diversity is very important to us. It's the lifeblood of our business — especially because we're serving publishers in those communities in big way. And moreso, we think you get the best product, thoughts, and ideas from a diverse workforce, and Houston fits right into that mold for us."

Walker shares more about his company's future, advice on IPO, and what all he's watching in adtech — from AI to streaming — on the podcast. Listen to the interview below — or wherever you stream your podcasts — and subscribe for weekly episodes.


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U.S. News names 5 Houston suburbs as the best places to retire in 2026

Retirement Report

Houston-area suburbs should be on the lookout for an influx of retirees in 2026. A new study by U.S. News and World Report has declared The Woodlands and Spring as the fourth and fifth best cities to retire in America, with three other local cities making the top 25.

The annual report, called "250 Best Places to Retire in the U.S. in 2026" initially compared 850 U.S. cities, and narrowed the list down to a final 250 cities (up from 150 previously). Each locale was analyzed across six indexes: quality of life for individuals reaching retirement age, value (housing affordability and cost of living), health care quality, tax-friendliness for retirees, senior population and migration rates, and the strength of each city's job market.

Midland, Michigan was crowned the No. 1 best place to retire in 2026. The remaining cities that round out the top five are Weirton, West Virginia (No. 2) and Homosassa Springs, Florida (No. 3).

According to U.S. News, about 15 percent of The Woodlands' population is over the age of 65. The median household income in this suburb is $139,696, far above the national average median household income of $79,466.

Though The Woodlands has a higher cost of living than many other places in the country, the report maintains that the city "offers a higher value of living compared to similarly sized cities."

"If you want to buy a house in The Woodlands, the median home value is $474,279," the city's profile on U.S. News says. "And if you're a renter, you can expect the median rent here to be $1,449." For comparison, the report says the national average home value is $370,489.

Spring ranked as the fifth best place to retire in 2026, boasting a population of more than 68,000 residents, 11 percent of whom are seniors. This suburb is located less than 10 miles south of The Woodlands, while still being far enough away from Houston (about 25 miles) for seniors to escape big city life for the comfort of a smaller community.

"Retirees are prioritizing quality of life over affordability for the first time since the beginning of the COVID-19 pandemic," said U.S. News contributing editor Tim Smart in a press release.

The median home value in Spring is lower than the national average, at $251,247, making it one of the more affordable places to buy a home in the Houston area. Renters can expect to pay a median $1,326 in monthly rent, the report added.

Elsewhere in Houston, Pearland ranked as the 17th best place to retire for 2026, followed by Conroe (No. 20) and League City (No. 25).

Other Texas cities that ranked among the top 50 best places to retire nationwide include Victoria (No. 12), San Angelo (No. 28), and Flower Mound (No. 37).

The top 10 best U.S. cities to retire in 2026 are:

  • No. 1 – Midland, Michigan
  • No. 2 – Weirton, West Virginia
  • No. 3 – Homosassa Springs, Florida
  • No. 4 – The Woodlands, Texas
  • No. 5 – Spring, Texas
  • No. 6 – Rancho Rio, New Mexico
  • No. 7 – Spring Hill, Florida
  • No. 8 – Altoona, Pennsylvania
  • No. 9 – Palm Coast, Florida
  • No. 10 – Lynchburg, Virginia
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This article originally appeared on CultureMap.com.

Micro-nuclear reactor to launch at Texas A&M innovation campus in 2026

nuclear pilot

The Texas A&M University System and Last Energy plan to launch a micro-nuclear reactor pilot project next summer at the Texas A&M-RELLIS technology and innovation campus in Bryan.

Washington, D.C.-based Last Energy will build a 5-megawatt reactor that’s a scaled-down version of its 20-megawatt reactor. The micro-reactor initially will aim to demonstrate safety and stability, and test the ability to generate electricity for the grid.

The U.S. Department of Energy (DOE) fast-tracked the project under its New Reactor Pilot Program. The project will mark Last Energy’s first installation of a nuclear reactor in the U.S.

Private funds are paying for the project, which Robert Albritton, chairman of the Texas A&M system’s board of regents, said is “an example of what’s possible when we try to meet the needs of the state and tap into the latest technologies.”

Glenn Hegar, chancellor of the Texas A&M system, said the 5-megawatt reactor is the kind of project the system had in mind when it built the 2,400-acre Texas A&M-RELLIS campus.

The project is “bold, it’s forward-looking, and it brings together private innovation and public research to solve today’s energy challenges,” Hegar said.

As it gears up to build the reactor, Last Energy has secured a land lease at Texas A&M-RELLIS, obtained uranium fuel, and signed an agreement with DOE. Founder and CEO Bret Kugelmass said the project will usher in “the next atomic era.”

In February, John Sharp, chancellor of Texas A&M’s flagship campus, said the university had offered land at Texas A&M-RELLIS to four companies to build small modular nuclear reactors. Power generated by reactors at Texas A&M-RELLIS may someday be supplied to the Electric Reliability Council of Texas (ERCOT) grid.

Also in February, Last Energy announced plans to develop 30 micro-nuclear reactors at a 200-acre site about halfway between Lubbock and Fort Worth.

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This article originally appeared on our sister site, EnergyCapitalHTX.com.

Houston falls from top 50 in global ranking of 'World's Best Cities'

Rankings & Reports

Houston is no longer one of the top 50 best cities in the world, according to a prestigious annual report by Canada-based real estate and tourism marketing firm Resonance Consultancy.

The newest "World's Best Cities" list dropped Houston from No. 40 last year to No. 58 for 2026.

The experts at Resonance Consultancy annually compare the world's top 100 cities with metropolitan populations of at least 1 million residents or more based on the relative qualities of livability, "lovability," and prosperity. The firm additionally collaborated with AI software company AlphaGeo to determine each city's "exposure to risk, adaptation capacity," and resilience to change.

The No. 1 best city in the world is London, with New York (No. 2), Paris (No. 3), Tokyo (No. 4), and Madrid (No. 5) rounding out the top five in 2026.

Houston at least didn't rank as poorly as it did in 2023, when the city surprisingly plummeted as the 66th best city in the world. In 2022, Houston ranked 42nd on the list.

Despite dropping 18 places, Resonance Consultancy maintains that Houston "keeps defying gravity" and is a "coveted hometown for the best and brightest on earth."

The report cited the Houston metro's ever-growing population, its relatively low median home values ($265,000 in 2024), and its expanding job market as top reasons for why the city shouldn't be overlooked.

"Chevron’s shift of its headquarters from California to Houston, backed by $100 million in renovations, crowns relocations drawn by record 2024 Port Houston throughput of more than four million containers and a projected 71,000 new jobs in 2025," the report said.

The report also draws attention to the city's diversity, spanning from the upcoming grand opening of the long-awaited Ismaili Center, to the transformation of several industrial buildings near Memorial City Mall into a mixed-use development called Greenside.

"West Houston’s Greenside will convert 35,000 square feet of warehouses into a retail, restaurant and community hub around a one-acre park by 2026, while America’s inaugural Ismaili Center remains on schedule for later this year," the report said. "The gathering place for the community and home for programs promoting understanding of Islam and the Ismaili community is another cultural jewel for the country’s most proudly diverse major city."

In Resonance Consultancy's separate list ranking "America's Best Cities," Houston fell out of the top 10 and currently ranks as the 13th best U.S. city.

Elsewhere in Texas, Austin and Dallas also saw major declines in their standings for 2026. Austin plummeted from No. 53 last year to No. 87 for 2026, and Dallas fell from No. 53 to No. 78.

"In this decade of rapid transformation, the world’s cities are confronting challenges head‑on, from climate resilience and aging infrastructure to equitable growth," the report said. "The pandemic, long forgotten but still a sage oracle, exposed foundational weaknesses – from health‑care capacity to housing affordability. Yet, true to their dynamic nature, the leading cities are not merely recovering, but setting the pace, defining new paradigms of innovation, sustainability and everyday livability."

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This article originally appeared on CultureMap.com.