Investors are clamoring for commercial real estate in markets that bounced hardest in the high-tech-boom-and-bust earlier this decade. This time around, however, cities like Austin, Texas and Portland, Ore. are developing more diverse local economies less reliant on software companies.

Investors and real estate service providers say these dot.com survivors retain virtually all of the qualities that drew knowledge firms in droves. Those attributes include good universities, a young populace with high education levels, and a vibrant culture to help attract and retain employees.

“They’re not technology centers, they are innovation centers,” says Ross Moore, vice president and director of market and economic research for Boston-based Colliers International. “The key is lots of smart people and lots of great universities. They all have that in common, and they attract young, smart people, which is where you go for new ideas.”

Moore considers Austin, Boston and Portland to have been the top high tech markets outside of California’s Silicon Valley. “Over the last five years, it’s remarkable how those markets have all adapted,” he says.

All of the former dot-com boom markets experienced office rent growth and declining vacancy rates in the 12 months that ended March 31, according to Boston-based Property & Portfolio Research. Vacancy rates in the first quarter ranged from a low of 12.6% in Seattle to a high of 18.7% in Boston. Austin posted a vacancy rate of 13.3%, down from 17.1% one year earlier, with rents climbing 13.7% over year-ago figures.

Austin leads job growth among the 54 metros tracked by Property & Portfolio Research, adding 30,900 jobs in the 12 months that ended March 31 for a growth rate of 4.3%. That compares with a national job creation rate of 1.4% for the same period. What’s more, Austin’s new jobs are in a variety of fields including government, health care, financial services and hospitality. Other dot.com veterans, including Portland, are experiencing a similar diversification beyond high tech in their employment growth.

Those growth trends are powerfully attractive to investors. So are barriers to entry by competitors, which in Austin include limitations on new big-box retail and a strenuous development approvals process. In Portland, new development is held in check by an Urban Growth Boundary, a geographic boundary set by Oregon municipalities to prevent sprawl and encourage density.

“It really does provide some certainty as to how fast or how slow growth can occur, and encourages infill and use of the infrastructure that already exists,” says Pam Baker, an investment specialist at Colliers International in Portland. “Sprawl is not an option.”

Pension funds and other investors looking for portfolio plays have fewer deals to choose from in these small markets, but that adds to their appeal by creating additional barriers to entry. By size, Austin is a secondary market with a metro population of about 1.5 million. The city’s entire office inventory is just less than 39 million sq. ft., with only 8.4 million sq. ft. in the central business district. By comparison, Houston has nearly 36 million sq. ft. of office in its CBD alone, according to Grubb & Ellis.

Despite its size, Austin has attracted some of the world’s largest investment groups. Earlier this month, a partnership led by Los Angeles-based Thomas Properties Group Inc. (NASDAQ: TPGI) closed on its $1.15 billion purchase of the former Equity Office Properties Trust portfolio in Austin from The Blackstone Group. The 10-building, 3.5 million sq. ft. deal marked the city’s largest transaction by dollar volume.

“The Austin market has historically demonstrated a resilience atypical of other U.S. markets, where it continues to show net absorption even through the downturns,” says John Cischo, executive vice president for development at Thomas Properties. “Businesses want to be in Austin because their employees are going to be happy there.”

Foreign investors are staking claims in Austin as well. San Diego-based Constellation Property Group is preparing to launch a residential condominium development on the south bank of the Colorado River in downtown Austin. Eugene Marchese, the company’s president, says nearly half of the project’s development capital is Australian.

Employment gains are driving Austin’s real estate investment activity, Marchese says. Job growth is a good barometer of the local economy’s strength, suggesting good demand for housing. Austin’s concentration of young professionals is particularly promising for developers of high-rise urban residential properties, he says. “Markets like Austin are a particular demographic that appeal to our type of product,” he says. “We’re excited about those markets where that demographic is healthily employed and looking to the future.”

With the rise of service industry jobs and other non-manufacturing employers, there is little to tie companies to a particular market beyond the preferences of its customers and employees. For that reason, America’s innovation centers are in a good position to attract new companies and drive demand for commercial real estate.

“People can live wherever they want,” says Baker, the Portland broker. “The jobs have to follow the people.”